key: cord-0042889-mw0czv5a
authors: VISSCHER, H.
title: PALAEOBOTANY OF THE MESOPHYTIC III: PLANT MICROFOSSILS FROM THE UPPER BUNTER OF HENGELO, THE NETHERLANDS
date: 2013-11-01
journal: Plant Biol (Stuttg)
DOI: 10.1111/j.1438-8677.1966.tb00236.x
sha: 97f77d81263d7f34ce0275c6cd7d410ce80e6ae3
doc_id: 42889
cord_uid: mw0czv5a

The Upper Bunter palynological assemblage described includes 54 species, assigned to 29 genera. Seven genera (Scabratisporites, Guttatisporites, Lapposisporites, Pseudogravisporites, Paralundbladispora, Taeniaepollenites and Tubantiapollenites) and 39 species are new; three generic descriptions are emended (Apiculatasporites, Colpectopollis and Angustisulcites) and three new combinations are proposed. Bisaccate pollen grains average 84 %; within this group no Upper Permian elements could be demonstrated. The assemblage is compared with other European Lower and Middle Triassic assemblages; there are no close similarities to assemblages outside Europe.

As a result of the accelerated development of Lower Mesophytic palynology during the last few years, even the conclusions of recent investigations may soon become obsolete.

By starting our studies in Triassic palynology we suspected the existence of important floristic differences between the European Upper Permian and Lower Triassic series. In order to prove this suspicion we had to continue and to revise the investigations carried out by FREUDENTHAL (1964) . Under the direction of Dr. W. Klaus, Vienna, we trained in recognizing Upper Permian sporae dispersae in order to be able to make comparisons with Lower Triassic assemblages. These were investigated from Upper Bunter evaporites and pelites.

The samples studied originate from the core of a drill hole situated in the exploited part of the Hengelo salt-deposits, south of the city of Hengelo in the province of Overijssel (situation: Cox 1963, Fig. 2) . The boring was carried out in 1953 by the Koninklijke Nederlandsche Zoutindustrie (Royal Dutch Salt Industry) in behalf of the construction of well 31 (situation: Cox 1963, Figs. 4, 5) . In this paper it will be indicated as "Boring 31, K.N.Z., Hengelo". The investigations were performed in the Palaebotanical laboratories of the Botanical Museum and Herbarium of the State University, Utrecht, under the direction of Dr. F. P. Jonker, professor of Special Botany.

In a large part of Europe the Upper Permian sediments contain similar palynological assemblages. Apart from local differences the mi~rofloras are identical both in the German Basin and in the Alpine regions.

This phenomenon can also be observed in the Upper Bunter. However, the microflora has changed into a totally new composition. Important Upper Permian elements like Nuskoisporites dulhuniyi, Lueckispontes virkkiae, Falcisporites zapfei, Limitisporites rectus, Klausipollenites schaubergeri, etc. have given way to Triadispora spec. div., Voltziaceaesporites heteromorpha, Angustisulcites klausii, Alisporites grauvogeli, etc. The regional similarities in the European (micro)flora during the Permian and Triassic periods indicate the existence of an important palaeo-phytogeographic unit. This may be of great interest for the knowledge about the Post-Carboniferous evolution of European palaeogeography. Up till now the available palynological data from Bunter sediments have been insufficient to introduce conceptions about the regional stratigraphical problems in this series.

The author was also unable to solve the local stratigraphical problem of the boundary between the Bunter and Muschelkalk; however, it is hoped that this investigation will contribute to the knowledge of the European Lower Triassic, which, until recently, remained undiscovered by palynology.

For a summary of the geological history and the tectonical relations in the eastern Netherlands we refer to PANNEKOEK et al. (1956) , FABER (1960) and HAANSTRA (1963) . Local geological data concerning the Hengelo region were published by Cox (1963) . He also summarized the historical, technical and economical aspects of salt production in the Netherlands.

The Hengelo salt-deposits are situated in the eastern part of the East Netherlands Triassic Swell, a tectonical unit extending in NW-SE direction from Eastern Flevoland in the former Zuiderzee to the Dutch-German border (PANNEKOEK et al. 1956, Fig. 2; HAANSTRA, 1963, Fig. 13 ). This unit consists mainly of Bunter (Buntsandstein) sediments with locally some remains of Muschelkalk and Liassic. These sediments are unconformably covered by Tertiary and Quaternary sands, sandy clays, gravels and peats. The eastern part of the unit is bounded by a zone of Lower Cretaceous, east of which we find the Munster Basin (PANNEKOEK et al. 1956, Fig. 17; FABER 1960, Fig. 175) .

The Bunter is considered to be a lithostratigraphical series.

Besides the general geolol9cal publications by PANNEKOEK et at. ( ), FABER (1960 and HAANSTRA (1963) one has to take resource to the more detailed research in the German area. BOiGK (1959) and TRUSHEIM (1963) have tried to build up a lithostratigraphical classification of the Bunter. Also the eastern Netherlands have been covered by their studies. The same applies to the sedimentological approach by SINDOWSKI (1957) . n a great part of the Netherlands the Bunter appeared to exist in the subsoil. However, important variations in thickness have been proved (FABER 1960, fig. 91 ). The coarse of the isopaches in Western Germany has been shown by TRUSHEIM (1963, fig. I) . In the area of the East Netherlands Triassic Swell the thickness of the Bunter increases in SE direction. Near Hengelo the sediments amount to 900 rn.

The Bunter is subdivided into the Lower-, Middle-and Upper Bunter. There is no unanimity about the limits of these subdivisions (TRUSHEIM 1963) . As the samples investigated have been taken from the Upper Bunter and the Lower Muschelkalk it seems useful to treat briefly the problems about the boundaries between Middle Bunter and Upper Bunter and between Upper Bunter and Muschc1kalk. In the Netherlands one usually starts the Upper Bunter with the Rot salt deposits. Also BOICK (1959) takes this view with regard to his subdivision of the German Bunter. The Rot is considered identical with the Upper Bunter and can be divided into the Rot salinar and the younger Rot pelites. The underlying Solling Group belongs to the Middle Bunter. Another boundary has been proposed by TRUSHEIM (1963) . Both the Solling and the Rot belong to the Upper Bunter; so the latter cannot be considered identical with the Rot. The boundary between the upper part of the Middle Bunter, the Hardegsen Group, and the Solling Group is marked by an uncomformity ("H-Diskordanz") whose occurrence has been demonstrated from the Dutch-German border up to Thiiringen and which can be correlated with the well-known fossil land surface in southern Germany. It may be regarded as the most important hiatus within the Bunter, if not within the whole German Triassic (TRUSHEIM 1963, figs. 2, 8) . Because of the comparatively small regional extension of the Rot salinar we prefer the "H-Diskordanz" as a criterion for the boundary between the Middle Bunter and the Upper Bunter. Unlike the interpretation by the K.N.Z. we consider the red sandy shales underlying the salt deposits to be the Upper Bunter (Solling Group; compare Table 1) .

Though the upper part of the Rot pelites may already be calcareous and dolomitic, the base of the German Muschelkalk is characterized by a yellowish crystalline limestone layer, often developed as a conglomerate. This layer starts the so-called Wellenkalk facies (BOIGK 1959) . In the eastern Netherlands, however, the boundary between the Bunter-and the Muschelkalk series cannot be drawn with the same accuracy. Usually the differences in colour of the calcareous shales will settle the matter; the Rot is brownish, the Muschelkalk greyish (FABER 1960) .

In the stratigraphical section ( Table 1 ) the boundary between the Upper Bunter and Muschelkalk has been copied from the interpretation by the K.N.Z., though outstanding lithological differences could not be demonstrated.

Apart from some experiments with other techniques the sampledigestion technique employed in preparing the samples has been as follows:

The samples were pulverized. Depending on the presence of NaCl or CaC03 the powder was boiled in Water or treated with diluted HCl respectively. The residue was placed in a,45 % HF solution for 24-48 hours. In some cases treatments with HCl were added to stimulate the solubility of the Si02• The effect of the HF was hampered by a film of fluor silicates around the Si0 2 particles. HCl dissolved the fluor silicates. Also, after the HF treatment a wash with HCl i. to follow. Since many samples appeared to contain a great deal of anhydrite or gypsum it was necessary to practice gravity separations For this separation a solution of ZnBr in 10 % HCl was used.

For counting microscopic slides were made from the concentrated fossil preparations, using glycerine. In order to study and describe the various species we used single grain slides made according to the preparation method of PUNT (1962) which are numbered 3l-HV-Ol, 31-HV-02, etc. They are stored in the Palaeobotanical laboratories of the Botanical Museum and Herbarium of the State University, Utrecht, the Netherlands.

We have investigated 43 core-samples from the boring 31, K.N.Z., Hengelo; they originate both from the Upper Bunter and the Lower Muschelkalk sediments (Table 2 ). In the latter no pollen and spores could be indicated (samples [1] [2] [3] [4] [5] [6] . Neither did the reddish Fe 3 +containing layers yield any microflora. The calcareous shale of sample 8 and the greyish sandy shales of samples 17, 20 and 26 contained some badly conserved pollen grains and spores. This also applies to the greyish shales of the upper part of the Rot salinar (samples 31 and 33). Five salt layers more or less mixed with clay and anhydrite can be distinguished (Table 1) . They contain sporae dispersae in In general the Rot pollen is badly preserved. A sufficient number of rather well-preserved pollen grains, necessary for studying and describing the species, has been found only in the relatively rich preparations. Unlike the pollen, the spores are usually well preserved. They always occur in very low percentages.

The quantitative analysis has been based on the 54 formspecies described in this paper.

The qualitative distribution of these species within the various pollen and spores bearing samples is shown in Table 3a .

Very few samples appeared to contain well preserved specimens, which is essential to detailed counting. Sample 37 turned out to contain a relatively rich microflora. Table 3b reproduces a counting based on this sample. In order to obtain the many low percentages it has been necessary to choose a high pollen sum (= 1000 determinable pollen grains and spores). On account of our observations we believe the percentages of this sample to be representative for the entire Rot salinar. The many gaps in Table 3a are due to the relatively smaller number of determinable pollen grains and spores.

It has been impossible to establish whether the percentages of Table 3b also apply to the samples 17, 20 and 26, which were taken from the Rot pelites. However, the percentages of sample 37 do certainly not apply to the microflora from the calcareous shale of sample 8 (upper part of the Rot pelites, transition to the Lower Muschelkalk). Here too we are dealing with a very poor and badly preserved microflora; however, a counting is reproduced in order to get an impression of the changed percentages (Table 3c) .

As no important microfloristic changes were demonstrated within the Rot salinar it is sufficient to discuss the differences between Rot salinar and Rot pelites. A comparison of the percentages of sample 8 (calcareous shale in the upper Rot pelites) with the percentages of sample 37 (representative for the Rot salinar) reveal some striking differences (Table 3b, The different character of sample 8 is specially owing to the increased percentage of Angustisulcites klausii at the cost of Voltriaceaesporites heteromorpha and Triadispora crassa.

In view of the very poor data obtained from the samples 17, 20 

Voltziaceaesporites heteromorpha. + + + + + + + + + + + + + + 21.0 II Alispori tes microreticulatus + + + + + + + + 0.7 Alisporites grauvogeli . + + + + + + + + + + + + + + 6.7 10 Colpectopollis ellipsoideus. . + + + + + + + + + + + + + + The palynological investigations in the Dutch Rot salinar were started by FREUDENTHAL (1964) . He studied samples from another K.N.Z. drill hole (69). The average quantitative distribution of sporae dispersae in the Rot, as given by Freudenthal, is reproduced in Table 4 .

By far the greatest part of the Rot microflora was supposed to consist of components that play already a more or less important part in the European Upper Permian (group 1). We have to refute this concept with emphasis; the presence of Upper Permian saccate pollen could be demonstrated neither in Freudenthal's slides nor in our own preparations. Also the presence of group 2 and group 3 in the Rot salinar is rather unlikely (Falcisporites staplini unequals Triadispora staplini).

Considering the species described by Freudenthal (group 4) only Falcisporites? grandis (= Angustisulcites grandis) and Angustisulcites klausii could be maintained. Our concepts with regard to the systematical positions of Freudenthal's species will be discussed in the systematical part of this paper.

Even after a "systematical revision" it has not been possible to compare Freudenthal's data with the results of our investigations. However, we are of opinion that there are no appreciable differences between the spectra of the two borings.

The ratio between striate pollen and non-striate pollen in the counting of sample 37 (approx. 1: 2) differs from the ratio mentioned by Freudenthal (8: 91) . Besides considering Illinites and Angustisulcites as striate pollen, this difference is attributable to the higher pollen sum. This may also explain the more prominent percentages of Sporites.

Similarities to Lower Triassic palynological assemblages outside Europe, for example Canada (JANSONIUS 1962) and Australia (BALME 1963) , can only be found at a generic level. So comparisons can be restricted to some European assemblages.

KLAUS (1964) investigated the characteristic microflora of German and French Upper Bunter sediments and also that of the Alpine Upper "Werfener Schichten", which can be correlated with the Upper Bunter. He also studied samples from German, French and Italian Middle Muschelkalk.

Finding characteristic assemblages in Upper Permian, Upper Bunter, Middle Muschelkalk and Keuper, Klaus states that sediments of these series can be distinguished palynologically. Table 5 shows a comparison with the Bunter and Muschelkalk assemblages described by KLAUS (1964) . Three groups of species can be distinguished:

1. Species occurring both in the Upper Bunter (possibly also in the Middle Muschelkalk) studied by Klaus and in the Hengelo Rot group. The regional distribution of these species appears to include the eastern Netherlands. centage of this species in the upper part of the Rot pelites (sample 8).

It is of great interest to compare the quantitative distribution of the species of Triadispora (Table 6 ): Triadispora staplini is even more frequent in Klaus' samples. In the Hengelo Rot, however, it is fairly uncommon.

Klaus does not mention the avarage of Triadispora falcata, known from the Upper Bunter. In the Hengelo assemblage this species is very rare. Triadispora epigona and Triadispora plicata are important elements of the Middle Muschelkalk assemblages from Kochendorf (Germany), Sarralbe (France) and Recoaro (Italy). However, they also exist in low percentages in the Hengelo Rot Group.

Considering the existence of progressive transitions in the Triadispora-groupat least in the Hengelo assemblage -these species may originate from the same conifer species. But in this case the differences in quantitative distribution are still more striking, and besides biostratigraphical and palaeo-phytogeographical aspects one has to reckon with phylogenetic considerations (compare p. 350).

REINHARDT (1964a, b) described some species from the Lower Rot of Thiiringen. The following elements of this incomplete assemblage can also be found in the Hengelo Rot:

Verrucosisporites jenensis Alisporites microreticulatus Nuskoisporites muelleri (= Triadispora muelleri) There are no resemblances to the Middle Bunter microflora described by SCHULZ (1964) . In future palynology may provide the possibilities to demonstrate the important "H-Discordanz" (p. 318) between Middle and Upper Bunter biostratigraphically. Remarks and comparisons: Some spores considered as Calamaspora have been found in sample 34. Because of the few specimens found and the bad preservation it has been impossible to compare our forms with the numerous species of Calamaspora mentioned in the palynological literature. Calamaspora sp. possesses an irrigular, but fundamentally circular outline; diameter approx. 60 ft. Exine smooth with fine infrastructure; thickness approx. 1 ft. Length of the Y-mark rays approx. 4/5 of the spore radius; usually the sutures are widely opened. Strongly folded. Calamaspora sp. differs from Calamaspora nathorstii (Halle 1906) Klaus 1960 , which is important to Upper Triassic and Lower Jurassic stratigraphy, by its bigger size and its thicker exine.

Psilatriletes (van der Hammen 1954) ex Potonie 1956 Type species: Psilatriletes (al. Punctatisporites'i detortus (Weyland & Krieger 1953 ) Potonie 1965 WEYLAND and KRIEGER 1953, t. 14, f. 24. Psilatriletes triassicus n. sp. (Loose 1932 ) Ibrahim 1933 POTONrE, IBRAHIM and LOOSE 1932, t. 18, f. 47; photo after type in POTONIE and KREMP 1955, t. 14, f. 214. 328 H. VISSCHER Diagnosis: Spores trilete, azonal, with approx. circular equator. Exine ornamentated with more or less regularly placed tapering or rather blunt echinae; height 0.5-1.5 fJ. The trilete rays are often indistinct and invisible by folding; they do not extend to the equator.

Remarks and comparisons: By describing Apiculatasporites IBRAHIM (1933) has chosen a trilete type species. Consequently afterwards this type species has been placed in trilete genera, viz. Apiculatisporites (by LooSE 1934), Punctatisporites (by SCHOPF, WILSON and BENTALL 1944) , Spinosospontes (by KNOX 1950) and Planisporites (by POTONIE and KREMP 1955) . However Apiculatisporites includes megaspores (compare POTONIE 1956, p. 30) ; the usage of American authors considering apiculate forms to Punctatisporites is objectionable; the position of Spinososporites is discussed by POTONIE (1958, p. 21) ; the latter author also dealt with the relation Apiculatasporites-Planisporites (POTONIE 1960, p. 21 ). Yet LESCHIK (1956a) considers Apiculatasporites alete; because of the trilete type species this is not permissible. Apiculatasporites can be distinguished from Scrabratisporites n. gen. by its higher exinal elements ( > 0,5 fJ).

Apiculatasporites plicatus n. sp. Diagnosis: Spores trilete, azonal, with approx. circular equator; diameter 55-65 fJ (holotype 61 fJ). Exine, 1.5-2 fJ thick, with a rather regular but not very dense ornamentation of small echinae (basis diameter 1-2 fJ, height max. 1 fJ). Trilete rays approx. 2/3 of spore radius, accompanied by indistinct labra (2.5-3 fJ). Usually many compression folds.

Remarks and comparisons: Because of the strong folding the Y-mark is only occasionally recognizable. The holotype of A. plicatus, however, shows a rather distinct Y-mark. Apiculatasporites spinulistratus (Loose 1932) Ibrahim 1933 differs by the more densely placed echinae of which the height exceeds the diameter. Scabratisporites scabratus n. sp. possesses elements 0.5 fJ. Diagnosis: Spores trilete, azonal, with approx. circular equator. Exine ornamentated with more or less regularly distributed scabrae. Trilete rays not extending to equator. Usually folded.

Remarks and comparisons: Following STRAKA (1964, Fig. 16 ), we define scabrae as exinal elements with a height < 0.5 fJ. VAN DER HAMMEN (1954 , 1956a proposed the genus Scabratriletes to include scabrate, trilete microspores. POTONIE (1956) legitimated this name but at present Scabratriletes (van der Hammen 1954) ex Potonie 1956 includes megaspores with elements up to 50 fJ. Apiculatasporites Ibrahim 1933 emend. possesses elements > 0.5 fJ. The same applies to to Planisporites Knox 1950 emend. Potonie 1960 . Moreover the latter genus possesses a subtriangu1ar equator. At first sight Scabratisporites seems to have a rather smooth exine but with high magnification the scabra are visible. By these minute elements Scabratisporites can be distinguished from laevigate genera like Punctatisporites Ibrahim 1933 emend. Potonie & Kremp 1954 , Orbella Malavkina 1949 , Phyllothecotriletes Luber 1955 and Cyclinasporites Nilsson 1958 . Mariattisporites scabratus Couper 1958 is monolete.

Scabratisporites scabratus n. sp. Diagnosis: Spores trilete, azonal, with approx. circular equator; diameter 44-50 fJ (holotype 48 fJ). Exine 1.5-2 fJ in thickness, rather regularly ornamentated with scabrae which have the shape of coni. Trilete rays of unequal length, the longest ray never exceeds 3/4 of the spores radius.

Remarks and comparisons: The spores are mostly folded. S. scabratus differs from Apiculatasporites plicatus n. sp. by its smaller exinal elements.

Locus typicus: Boring 31, K.N.Z., Hengelo; depth 405.50 m (Rot salinar), Occurrence: Rot salinar of Hengelo; rare.

Remarks: A boundary between the subinfraturma Verrucati and the infraturma Murornati Potonie & Kremp 1954 cannot be drawn with accuracy. For example, the bigger verruca-like elements of Guttatisporites n. gen. seem to have developed by the growing together of some small elements. The general impression, however, remains verrucate. So we will give up the idea of considering such forms as Murornati, because within this infraturma the phenomenon of elements grown together is much more striking.

Verrucosisporites Ibrahim 1933 emend. Smith et al. 1964 Type species: Verrucosisporites (al. Sporites) oerrucosus (Ibrahim 1932 ) Ibrahim 1933 POTONI£., IBRAHIM and LOOSE 1932, 1. 15, f. 17 ; photo after the type in POTONI£. and KREMP 1955, 1. 13, f. 196 and in SMITH, BUTTERWORTH, KNOX and LOVE 1964, t . 3, f. 7. Remarks and comparisons: Our specimens well correspond to the specific description by REINHARDT (1964b) . An average of 50 verrucae can be counted on the spore outline; diametrically an average of 20. V. jenensis differs from Verrucosisporites reinhardtii n. sp. by possessing a thinner exine (respectively 3-4 ft and 6-7 ft).

Occurrence: Rot salinar of Hengelo; rare. Reinhardt mentions the species from the Lower Rot of Thuringen (Germany).

Verrucosisporites reinhardtii n. sp. Derivatio nominis: P. Reinhardt, Geologisches Institut der Bergakademie Freiberg, Germany.

Diagnosis: Spores trilete, azona1, with covex-subtriangular equator. Very thick exine (6-7 /J), with a dense ornamentation of polygonal verrucae (diameter 2.5-5 ft, height 1.5-2.5 ft; the bigger elements only at the distal surface). An average of 37 verrucae can be counted on the spore outline, diametrically about 15-20. Between the verrucae a polygonal negative reticulum is visible. Trilete rays of the distinct V-mark extend to 2/3-3/4 of the spore radius. Known size range 65-72 II (holotype 67ft). Diagnosis: Spores trilete, azonal, with approx. circular equator.

Exine, 1.5-2 fl thick, distally covered by a dense irrigular ornamentation of polygonal verrucae (basis 1.5-3.5 fl, height 1.5-2 fl); proximally smaller (1.5-2 fl), regularly distributed verrucae are dominating; here a polygonal negative reticulum appears. Usually the verrucae are flattened, occasionally they are slightly gemmate. Equatorially 40-50 elements can be counted, diametrically 15-20. Distinct Y-mark with rays extending to 3/4-2/3 of the spore radius. Known size range 65-70 fl (holotype 68 fl). Guttatisporites n. gen.

Type species: Guttatisporites guttatus n. sp., Plate II, Eigs, 1 A, B. Diagnosis: Spores trilete, azonal, with approx. circular to convexsubtriangular equator. Exine densely covered by very irregularly shaped verruca-like elements. These elements show polygonal to crenulate outlines; they vary in size and shape. Bigger elements seem to have developed by the growing together of some small elements; they are mainly restricted to the distal spore surface. Between the elements a negative reticulum appears.

In spite of the bigger, complex elements Guttatisporites presents itself as a verrucate genus. It differs from Verrucosisporites Ibrahim 1933 emend. Smith et al. 1964 in that it possesses the characteristic exinal elements described. Diagnosis: Spores trilete, azonal, with circular equator. Diameter of holotype 95 fl. Exine, approx. 3.5 fl thick, densely covered by very irregularly shaped, low (approx. 1.5 fl) verruca-like elements; these show polygonal to slightly crenulate outlines; they vary in size and shape (basis 3-4 fl). Bigger elements, both proximally and distally existing, seem to have developed by the growing together of some smaller elements. The elements are unflattened, they possess a faint irregular relief. The narrow pits (approx. 0.5 fl) between the elements form a negative reticulum. Rather distinct V-mark with trilete rays extending to 3/4-2/3 of the spore radius.

Remarks and comparisons: G. guttatus strikes by its truly circular equator; also specimens which are not proximo-distally flattened show a circular outline, this suggest a sphaerical shape of the spores. Guttatisporites microechinatus n. sp. differs by its small echinae superposed on the verrucae. Guttatisporites elegans n. sp. shows a subtriangular equator, longer trilete rays and bigger elements. Diagnosis: Spores trilete, azonal, with convex-subtriangular equator.

Diameter of holotype 72 fl. Exine densely covered by very irregularly shaped verruca-like elements; these show polygonal to crenulate outlines; they vary in size and shape (basis 2-8 fl, height 1,5-2 fl); proximally only smaller elements can be found, distally the bigger elements predominate. The latter seem to have developed by the growing together of some small elements. The elements are unflattened, they possess a faint irregular relief. The trilete rays of the distinct V-mark extend to the equator.

Remarks and comparisons: The shape of G. elegans seems related to an undescribed species illustrated by COUPER and HUGHES (1963, t. 1, f. 3) from the Dutch Lower Liassic; this species differs by the still more remarkably grown together elements. Guttatisporites guttatus n. sp. differs by its circular equator, by the shorter trilete rays and by the smaller average size of the verrucae. Guttatisporites microechinatus n. sp. possesses small echinae superposed on the verruca-like elements. Diagnosis: Spores trilete, azonal, with approx. circular equator. Diameter of the holotype 89 fl. Exine, approx. 4.5 fl thick, densely covered by very irregularly shaped, low (approx. I fl) verruca-like elements; these show polygonal to strongly crenulate outlines; they differ strongly in size and shape. Bigger elements, existing both proximally and distally, seem to have developed by the growing together of some smaller elements. The elements are unflattened, they possess an irregular relief. Sometimes echina-like differentiations are superposed on the verrucae; usually one element bears one echina, but bigger elements may also possess two or more echinae. The narrow pits (approx. 0.5 fl) between the verrucae form a negative reticulum. The trilete rays extend to the equator.

Remarks and comparisons: The superposed echinae are only visible with high magnification. G. microechinatus differs from Guttatisporites guttatus n. sp. and Guttatisporites elegans n. sp. by its characteristic echina-bearing verrucae. Remarks and comparisons: Although the still connected spores do not show a tetrad mark the trilete character of Lapposisporites is indicated by the tetrahedral tetrads. The tetrads can be fossilized in three fundamental positions (Fig. 7) . Superficially the genus reminds one of Q,uadrisporites Hennelly 1958 emend. Potonie & Lele 1961 ; this genus, however, differs by its tetragonal (square) or rhombic tetrads which suggest a monolete character. Moreover, investigations by ERDTMAN (1945) on the occurrence of tetrads of recent pollen show the exceptional appearance of both tetrahedral tetrads and tetragonal or rhombic tetrads within one plant species. Ricciisporites Lundblad 1954 emend. Lundblad 1959 Diagnosis: Spores trilete, azonal, apiculate, still connected in tetrahedral tetrads. Exine densely ornamentated by long echinae (6-7 fl). Biggest dimension of holotype 120 fl.

Comparisons: L. villosus differs from Lapposisporites lapposus n. sp., Lapposisporites loricatus n. sp. and Lapposisporites armatus n. sp. by its striking echinate exine. Cingulum scabrate with small circumequatorially situated folds; cingulum 5-7 fl, wide. Trilete rays of the Y-mark extend into the cingulum; narrow labra.

Comparisons: D. caretteae reminds one of Densoisporites perinatus Couper 1958 (Jurassic -Lower Cretaceous) ; the latter species differs by its wider labra. Combined with a wider cingulum this also applies to Densoisporites fissus Reinhardt 1964 , which also possesses, like Densoisporites regularis Danze-Corsin & Laveine 1963 , trilete rays extending to the outer margin of the cingulum. Diagnosis: Spores trilete, zonal. Equator of spore body and outline of cingulum approx. circular to subtriangular. Exine laevigate to scabrate. Very narrow trilete sutures situated between strongly developed labra which form rather wide ridges with crenulate margins; they terminate abruptly just before the equator of the spore body.

Remarks and comparisons: The genus reminds one of Gravisporites (al. Cadiospora) sphaerus (Butterworth & Williams 1954 ) Bharadwaj 1954 , the type species of Gravisporites Bharadwaj 1954. This species, however, is characterized by a thickening of the equator of the spore (crassitudo). Pseudogravisporites does not show this equatorial thickening: the cingulum is lighter coloured than the exine of the spore body. Also Cadiospora Kosanke 1950 emend. Venkatachala & Bharadwaj 1964 is characterized by a thickened equatorial exine. Lycospora Schopf, Williams & Bentall 1944 emend. Potonie & Kremp 1954 includes smaller species with longer and narrower labra. Polimorphisporites Alpern 1958 , at least the type species Polymorphisporites laevigatus Alpern 1958 differs by its trilete rays of unequal length and its less pronounced labra.

Pseudogravisporites reticulatus n. sp. (holotype 61 ft). Exine laevigate to scabrate; distally low muri make a very vague reticulate structure. Very narrow trilete sutures situated between wide ridge-like labra (approx. 5 ft wide); the margins of the labra are slightly crenulate; they terminate abruptly just before the equator of the spore body.

Remark: The vague reticulate structure is only visible with phasecontrast microscopes. Diagnosis: Spores trilete, zonal; equator of spore body and outline of cingulum approx. circular; relatively small diameter (30-35 ft; holotype 32 ft). Exine probably finely scabrate. Trilete rays extend to the equator of the spore body; the sutures are situated between more or less wavy ridge-like labra.

Remarks and comparisons: The characteristics of A. tenuis are badly pronounced; the wavy trilete rays do not appear as clear dark differentiations like the V-mark of the Permian Anguisporites anguinus Potonie & Klaus 1954 Diagnosis: Spores trilete, zonal, usually still connected in tetrahedral tetrads. Equator of spore body approx. circular to subtriangular. Exine finely structured or infrastructured. Narrow cingulum, situated proximal of the equator. Proximal side with subpyramidal shape. The rare single specimens show a tetrad mark with thickened labra.

Remarks and comparisons: We consider the occurrence in still connected tetrahedral tetrads a generic characteristic; single spores are very rare. Superficially the tetrads remind one of tetrads of Circulina (Malavkina 1949) ex Klaus 1960 which is characterized, however, by a circumequatorial thinning of the exine. The cingulum of Paralundbladispora is clearly projecting. Moreover, the proximal side of Circulina is more rounded, it shows a very small V-mark. Lundbladispora Balme 1963, sometimes also occurring in tetrads, seems very related but differs by the truly equatorial cingulum and the eccentrically placed papillate intexine. Paralundbladispora quadriiuga n. sp. Diagnosis: Spores trilete, zonal, usually still connected in tetrahedral tetrads. Equator of spore body approx. circular to subtriangular. Exine scabrate to finely granulate; exine approx. 1 fl thick. Narrow cingulum, situated proximal of the equator. Proximal side subpyramidal. Single specimens show the tetrad mark with the thickened irregularly wavy labra which approximately extend to the equator (Plate IV, Fig. 5 ). Biggest dimension of the holotype 57 fl.

Remarks and comparisons: Because of the proximal position of the cingulum polar flattened specimens, both single spores and spores forming part of a tetrad do not show the narrow cingulum clearly. It appears as proximal folds parallel to the equator. Equatorially flattened specimens of the tetrads, however, demonstrate the cingulum very clearly. P. quadriiuga reminds one of Lundbladispora nejburgii Schulz 1964 which may be compared with the microspores of Pleuromeia rossica Nejburg 1960; it differs by occurring in tetrads and by slightly narrower labra. Paralundlbadispora vieta n. sp. differs by a thick infrastructured exine. Diagnosis: Spores trilete, zonal, only recognized in still connecting tetrahedral tetrads. Equator of spore body approx. circular to subtriangular. Exine 2.5-3 fl thick, smooth with fine infrastructure. Narrow cingulum, situated proximal of the equator. Proximal side of a single spore subpyramidal. The spores are strongly folded. Biggest dimension of holotype 66 /l,.

Remarks and comparisons: As for the visibility of the proximal cingulum, compare Paralundbladispora quadriiuga (remarks, p. 338). The lat.ter species differs from P. vieta by its thinner scabrate-granulate exine. Diagnosis: Spores trilete, zonal; equator of spore body and outline of zona approx. circular to subtriangular. Diameter (zona included) 70-80 /l, (holotype 75 fl). Exine of spore body 1.5-3 fl thick, proximally smooth, distally ornamentated by long echinae (basis 2-3 If" length 6-7 fl). Zona 3-5 fl wide, also covered by long echinae. Trilete rays extend to the equator of the spore body; they are accompanied by narrow, slightly thickened labra.

Remarks and comparisons: The long echinae may break easily during fossilisation. K. hystrix differs from Kraeuselisporites hoofddijkensis n. sp. by its longer echinac. Diagnosis: Spores trilete, zonal; equator of spore body and outline of zona approx. circular to subtriangular. Diameter (zona included) 55-70 p (holotype 59 p). Exine of spore body 2-4 p thick, proximally smooth with fine infrastructure, distally ornamentated by echinae. The echinae show a diverging variability in shape; elements with a wide basis (max. 4 p) show a polygonal outline, smaller elements (from 1 p) are more or less circular; length of echinae 2-3.5 u: Zona 2-2.5 p wide, also covered by echinae. Trilete rays extend to the equator of the spore body; they are accompanied by narrow slightly thickened labra which are fan-shaped at the ends.

Remarks and comparisons: The species shows an important variation in size and shape of the echinae; however, there is always progressive transition, so a specific separation does not seem desirable. K. hoofddijkensis differs from Kraeuselisporites hystrix n. sp. by its shorter echinae. Frequently there are tendencies to a release of the zona.

Locus typicus: Boring 31, K.N.Z., Hengelo; depth 405.50 m (Rot salinar). Occurrence: Most frequent zonal spore in the Hengelo Rot salinar; never high percentages. Also recognized in the overlying Rot pelites.

Saturnisporites Klaus 1960 Type species: Saturnisporites fimbriatus Klaus 1960, t. 32, f. 32, 33. Remarks and comparisons: Klaus (1960) dealt with the relation Aratrisporites Leschik 1956a -Saturnisporites Klaus 1960 ; he separates the genera strictly. Recently this subject was discussed again by BHARADWA] and SINGH (1964) ; they do not find any important differences. Because of differences existing in equatorial flattened specimens, however, we want to follow Klaus. In equatorial view Aratrisporites shows a slightly concave proximal outline (KLAUS 1960, t. 44, f. 41) ; Saturnisporites differs by a straight to slightly convex outline (Plate XIII, fig. 4 ). These differences suggest a different shape of the spores and justify a separation. We are not convinced of the zonal character of the genus.

Up till now both Saturnisporites and Aratrisporites have only been found in Upper Triassic assemblages; our findings indicate a still earlier appearance of these interesting monolete spores.

Saturnisporites praevius n. sp. Fig. 13 Diagnosis: Spores monolete, zonal (?), with elliptical equator. Proximal exine with fine infrastructure; the distal exine seems strongly Fig. 13 . Saturnisporites praeoius fibrous, it can easily be deformed, causing an irregular outline with projecting "fibres". Very narrow monolete suture accompanied by pronounced dark labra which extend into the "zona". "Zona" 6-9 fl wide. In equatorial view the proximal outline appears straight to slightly convex. Known size range 54-62 fl (holotype 59 fl).

Remarks and comparisons: Specimens of S. praeoius are always badly preserved; we are not convinced of the zonal character. Satumisporites fimbriatus Klaus 1960 Remarksandcomparisons: The V-mark does not appear in the proximal exoexine. Usually the recognized specimens of N. inopinatus are badly preserved. However, the holotype shows sufficient details to compare it with the Permian representatives of Nuskoispontes. In some aspects N. inopinatus reminds one of the American Nuskoisporites crenulatus Wilson 1962 which, however, possesses a deeply crenulate contact edge. Nuskoisporites triangularis (Metha 1944 SUBTURMA Disaccites Cookson 1947 INFRATuRMA Disacciatrileles (Leschik 1956a ) Potonie 1958 Voltziaceaesporites Klaus 1964 Type species: Voltziaceaesporites heteromorpha Klaus 1964, t. 2, f. 19. Voltziaceaesporites heteromoepha Klaus 1964 Fig. 15; Plate VIII, Figs. 3, 4, 5. Holotype: Voltziaceaesporites heteromorpha Klaus 1964, t Remarks: Our forms correspond to the specific description by KLAUS (1964) . Within the variation of V. heteromorpha monosaccate, trisaccate and platysaccoid forms are rather common. There are also divergences in the thickness of the proximal exine of the central body. Observed size range 70-135 fl.

Occurrence: V. heteromorpha is the most common species in the Hengelo Rot salinar; less frequent in the Rot pelites. Also known from French, German and Alpine Upper Bunter or equivalents (KLAUS 1964) . In Muschelkalk and Keuper assemblages the species may still be present in decreased percentages. Remarks and comparisons: Our forms correspond to the specific description by REINHARDT (1964a) . The very finely infrareticulate sacci are exceedingly striking; they are radially structured. Compared with the other bisaccate species from the assemblage described A. microreticulatus is remarkably dark-brown coloured. The fundamentally fusiform germinal area may show diverging shapes, due to fossilisation. In a few cases specimens with a clear reduced trilete mark in the proximal exoexine were recognized (Plate XIII, Figs. 2A, B) , there are no other differences with the dominant alete forms. This feature may suggest a trilete tendency within the variation of A. microreticulatus. Observed size range 68-128 ft.

The species differs from Alisporites grauvogeli Klaus 1964 by its characteristic infrareticulum and by a bigger average size.

Occurrence: Regularly recognized in the Hengelo Rot salinar; never in high percentages. REINHARDT (1964a) reports the species from the Lower Rot of Thuringen (Germany). Klaus 1964 Fig. l6b ; Plate XIV, Figs. 5, 6.

Holotype: Alisporites grauvogeli Klaus 1964, t. 4, f. 38. Remarks and comparisons: Our forms correspond to the specific description by KLAUS (1964) ; we observed a wider size range (40-80 ft, Klaus: 60-80 ft). The fundamentally fusiform germinal area may show diverging shapes due to fossilisation. Compared with Alisporites microreticulatus Reinhardt 1964a, A. grauvogeli possesses a considerably coarser infrareticulum.

Occurrence: Regularly recognized both in the Rot salinar and in the Rot pelites of Hengelo. KLAUS (1964) Pflug 1953, t. 17, f. 7, 8, 9. Diagnosis: Pollen bisaccate, alete. Elliptical outline both in polar view and in equatorial view; this is due to the original ellipsoid shape of the pollen grains. Central body with thickened proximal exoexine.

Sacci haploxylonoid, equatorially interconnected. Very indistinct distal germinal area which is fundamentally fusiform. Both the thickened proximal exine of the central body and the unthickened distal exine can be longitudinally folded. This happens very frequently in a very characteristic way (see remarks). Remarks and comparisons: PFLUG (1953) described his genus Colpectopollis as follows: "Mit Resten von Luftsacken, Germinalapparat besteht nur aus der Kammgerminal. Porus ruckgebildet", Within the assemblage described we found specimens which are well comparable with Pflug's illustrations of Colpectopollis and of his "Siegelsum M-Typus". However the author considers the "Kammgerminal" nothing but a longitudinal fold in the thickened proximal exine. Differences in the projection of the infrabaculate proximal exine cause a seeming ridge, split by a seeming crack (Fig. l7e) . Also the unthickened distal exine is sensitive to folding (Fig. 17b) . Specimens in polar view without any folding are very rare (Fig. l7c) . Specimens in equatorial view show clearly the thickened proximal exine and the elliptical outline (Fig. 17d) . Because of the original ellipsoid shape the pollen grains do not show any preference for their position during sedimentation; consequently they can be fossilized in diverging positions.

On account of our reconstructions (Fig. 17) we have to disagree with Pflug's concept of a germinal function of the longitudinal ridges; we also deny the existence of a "ruckgebildete Porus".

Although the presence of the characteristic folds is due to fossilisation the genus Colpectopollis can be maintained; the folds, combined with the ellipsoid shape are useful generic characteristics.

It seems likely that Unatextisporites Leschik 1956a also possesses a seeming crack (compare LESCHIK 1956a, t. 8, f. 7 with PFLUG 1953, t. 17, f. 15, 16 and our Plate IX, Fig. 3) .

Also torn specimens (Fig. l7a ) are frequent; they can be compared with Schismatosporites Nilsson 1958. The polar view, without folds, reminds one of Sulcatisporites Leschik 1956a emend. Bharadwaj 1962 which, however, possesses distally inclined sacci. The general shape of Ovalipollis Krutzsch 1955 emend. Klaus 1960 may be related, but according to Klaus (1960) Diagnosis: Pollen bisaccate, alete. Elliptical outline both in polar view and in equatorial view; this is due to the original ellipsoid shape of the pollen grain. Equator of the central body approx. circular to longitudinally elliptical. Central body with proximally thickened exine (3-3.5 p,). Sacci haploxylonid, equatorially interconnected. Very indistinct distal germinal area which is fundamentally fusiform. Both the thickened proximal exine of the central body and the unthickened distal exine can be longitudinally folded. This happens very frequently and in a very characteristic way (compare emended generic description, remarks.) Known size range 70-100 p, (holotype 77 p,).

Remarks and comparisons: Reconstructing the original shape of the pollen grain it has been demonstrated that the equatorial exine is not thickened (Fig. l7d) ; so in polar view the outline of the central body shows very indistinctly. This in contrast with Colpectopollis occupatus Pflug 1953. Locus typicus: Boring 31, KN.Z., Hengelo; depth 405.50 m (Rot salinar). Occurrence: Rot salinar of Hengelo; regularly recognized but never in high percentages. Also present in the upper part of the overlying Rot pelites; more frequent. Klaus 1960 Type species: Chordasporites singuliclzorda Klaus 1960, t. 33, f. 45. Remarks: Bisaccate pollen grains showing the striking exinal strand interconnecting the sacci may be considered monstrousities. In all probability the phenomenon of a chorda appears within several form-genera. Because of the important stratigraphical value of Chordasporites (KLAUS 1960 (KLAUS , 1964 , however, accidental deformations are out of the question. The occurrence of the genus is mainly restricted to Triassic assemblages (KLAUS 1960 (KLAUS , 1964 DE JERSEY 1962) but also in Upper Permian rare representatives of Chordasporites are to be expected (KLAUS 1963b Diagnosis: Pollen bisaccate, alete. Equator of central body usually transversely elliptical but occasionally tendencies to circular and even longitudinally elliptical outlines. Proximal exoexine finely infrareticulate to finely granulate at the proximal pole. Sacci haploxylonoid, hardly or not distally inclined, laterally not interconnected; meshes of the regularly shaped infrareticulum 2-3 fl wide. Distal germinal area more or less distinctly limited, lemniscatoid shape, usually accompanied by narrow transversal folds. Known size range 80-92 fl (holotype 84 fl).

Remarks and comparisons: Compared with most of the other bisaccate species in the assemblage described, the sacci of F. snopkooae are rather coarsely infrareticulate. Falcisporites ::::.apfei (Potonie & Klaus 1954) Leschik 1956b is very related, but this Upper Permian species differs by a still coarser infrareticulum which is irregularly and imperfectly shaped. Specimens with a transversely elliptical equator do not exist within the variation of F. zapfei.

FREUDENTHAL (1964) illustrates three specimens of "F. ::::.apfei"; one of them, however, must be considered to be F. snopkooae (t. 2, f. 2) ; the other two specimens belong to Paravesicaspora planderovae n. sp. (t. 2, f. 1, 3) .

F. snopkovae differs from Triadispora falcata Klaus 1964 by the absence of a tetrad mark and by its relatively coarse infrareticulum.

Type species: Paravesicaspora (al. Sulcatisporites) splendens (Leschik 1956b Remarks and comparisons: Because of fossilisation sometimes the lateral exoexinal saccus-interconnections are ruptured; in this case specimens with a more or less Falcisporites-like habitus can be formed (FREUDENTHAL 1964, t. 2, f. 3 : "Falcisporites zapjei"). These forms differ from Falcisporites zapfei (Potnie & Klaus 1954 ) Leschik 1956b and Falcisporites snopkovae n. sp. by a much finer saccus infrareticulum. P. planderovae also differs from Paravesicaspora splendens (Leschik 1956b) Klaus 1963a by a finer infrastructure of the bladders. Microcachryidites (Cookson 1947) ex Couper 1953 Type species: Microcachryidites antarcticus Cookson 1947, t . 14, f. 19. Klaus 1964 Fig. 21; Plate VII, Figs. 2A, B. Holotype: Microcachryidites doubingeri Klaus 1964, t. 3, f. 27. Remarks: Our specimens correspond to the specific description by KLAUS (1964) . The thick exine is very striking.

Occurrence: KLAUS (1964) reported M. doubingeri from French and Italian Muschelkalk assemblages. We recognized the species in very low percentages in the Hengelo Triadispora Klaus 1964 Type species: Triadispora plicata Klaus 1964, t. 2, f. 15. C(J) 

In 1958 KLAUS already reported the existence of bisaccate trilete pollen which should be characteristic for European Lower Triassic assemblages. In 1964 he described the genus Triadispora. Apart from abnormal forms ("Forma Y") KLAUS (1964) distinguished five different species: T. staplini (we do not consider T. staplini identical with Klausipollenites staplini Jansonius 1962), T. crassa, T. falcata, T. epigona and T. plicata. Moreover, a sixth species can be distinguished: T. muelleri (-Nuskoisporites muelleri Reinhardt and Schmitz in REINHARDT 1964b ).

In the assemblage described, more than 80 % of the Triadisporaforms belong to Triadispora crassa. The variation of this species turns out to be very diverging and includes amongst others progressive transitions to the other Triadispora-species (Fig. 22) . This may be an argument for placing these species within the variation of T. crassa, in order to avoid a subjective specific subdivision. For stratigraphical reasons, however, a separation remains desirable (compare p. 326). The variation of the genus Triadispora reminds one of the analogue divergences in the pollen in situ of Ullmannia frumentaria, investigated by GREBE and SCHWEITZER (1962) . A wide variation combined with the occurrence of abnormal forms is also demonstrated within the striate pollen studied by BHARADWA] (1962). Frequently a wide variation of recent coniferal saccate pollen is due to interspecific hybridizing. For example the hybrid Pinus uncinata X Pinus silvestris produces pollen grains possessing both abnormal shapes and varying dimensions compared with the parents (AYTUG 1962).

In the symposium "Evolution" (Amsterdam 1959) Sirks mentioned the Widespread opinion according to which interspecific hybridizing might be an important factor in plant evolution. The creation of botanical interspecific hybrids may lead to an explosion of new phenotypes (SIRKS 1960 ).

An evolutionary trend within the genus Triadispora might explain the differences in relative quantitative distribution of its species in other localities (compare p. 325). However, to prove this preliminary impression we need more data about the horizontal and vertical occurrence of this interesting genus.

FREUDENTHAL'S (1964) illustrations of his genus Eridospollenites are concerned with Triadispora. Limitisporites Leschik 1956b emend. Potonie 1958 differs from Triadispora by the presence of a structureless exoexinal area around the Y-mark (for the taxonomical problem with regard to Limitisporites, Jugasporites, Illinites and Eridospollenites we refer to the description of Illinites, p. 353). Klaus 1964 Holotype: Triadispora crassa Klaus 1964, t, 1, f. 2. Remarks and comparisons: In spite of distinguishing five more species of Triadispora the variation of T. crassa still remains very diverging (Fig. 22a) . This is mainly due to the multitude in transitional forms between this species and T. staplini, T. plicata, T. epigona, T. falcata and T. muelleri. As stratigraphical counter-arguments are lacking also monosaccate and platysaccoid forms are placed within T. crassa.

The presence of transveral folding has to be considered a secondary feature; both forms with one and with two folds can be found, but also folds in other directions appear frequently. However, the haploxylonoid T. falcata and its transitions may be more sensitive to compression folding.

Apart from the shape of the sacci there are also variations in size, V-mark development (trilete, reduced trilete, rarely monolete), distal bladder base (distinct or indistinct) and proximal exoexinal structure of cental body (tendency to plicate structure which results in T.

KLAUS (1964) mentioned already the occurrence of tetrads; Plate X, Figs. SA, B shows a well preserved example of T. crassa quadruplets. Table 7 shows the averages of the most prominent forms of Triadispora in the Hengelo assemblage. The remainder mainly consists of badly preserved indeterminable specimens, which mostly show lost sacci or a dissolved intexine. Also KLAUS (1964) reported the frequency of the latter phenomenon.

Occurrence: T. crassa is common in the Hengelo Rot salinar. In the upper part of the Rot pelites the species is less frequent. KLAUS (1964) reported T. crassa from the Vosges and from Thuringen, Triadispora staplini Klaus 1964 Fig. 22c ; Plate XII, Fig. 3 .

Holotype: Triadispora staplini Klaus 1964 , t. I, f. 5 (non Klausipollenites staplini Jansonius 1962 . KLAUS (1964) stated that the haploxylonoid forms of Triadispora should be identical with Klausipollenites staplini Jansonius 1962. Some of Jansonius' Canadian preparations, rich in K. staplini, are stored in Utrecht and the author restudied this species. He disagrees with Klaus' conception about its fundamental trilete character. In some rare cases faint lines may suggest an V-mark, but probably these are secondary phenomena. Furthermore the species possesses the characteristic thickened bladder base, already 352 H. VISSCHER reported by JANSONIUS (1962) . Because of the alete character the Canadian species cannot be placed within the genus Triadispora. So with regard to the European haploxylonoid Triadispora-forms the epithet staplini and Klaus' specific diagnosis remain useful. A new holotype has been chosen from Klaus' illustrations (KLAUS 1964, t. 1, f. 5) .

The position of Falcisporites staplini (Jansonius 1962) Freudenthal 1964 is not clear. Freudenthal does not illustrate this species and single grain slides are unavailable.

Only truly haploxylonoid forms without equatorial bladder interconnections are considered as T. staplini; for practical reasons transitions to T. crassa are considered as the latter species. Specimens with very small haploxylonoid sacci belong to T. epigona; in this case the transitions are considered as T. staplini. Transitions to T. plicata have not been recognized.

Occurrence: Very low percentages in the Hengelo Rot salinar; very frequent in the German, French, Italian and Austrian Upper Bunter assemblages investigated by KLAUS (1964) . Klaus 1964 Fig. 22f .

Holotype: Triadispora falcata Klaus 1964, t. 1, f. 6. Remarks and comparisons: Triadispora-forms conforming to the description of T. falcata have been demonstrated very seldom in the Hengclo assemblage. Well preserved specimens for using in single grain slides have not been found.

The presence of transversal folds is considered a secondary phenomenon (p. 351). However, the haploxylonoid Falcisporites-like sacci are sufficiently characteristic to maintain T. falcata. Transitions to T. crassa occur less seldom; they are considered as the latter species (FREUDENTHAL 1964, t. 1, f. 1: "Eridospollenites bentzi") . Occurrence : Very rare in the Hengelo Rot salinar. KLAUS (1964) also recognized the species in Upper Bunter assemblages. Triadispora Dluelleri (Reinhardt and Schmitz in REINHARDT 1964b) nov. comb. Fig. 22e ; Plate XII, Figs. 1, 2.

Holotype: Triadispora (al. Nuskoisporites) muelleri (Reinhardt and Schmitz in REINHARDT 1964b) nov. comb.; REINHARDT 1964b, t. 1, f. 5. Remarks and comparisons: Unlike REINHARDT (1964b) we consider T. muelleri a fundamentally trisaccate species. Via transitions it can be derived from T. crassa (Fig. 22) . T. muelleri differs from these transitional forms by its relatively bigger central body, by the less projecting oval sacci (in polar view), by the rather distinct bladder bases and by the very characteristic distal bladder interconnections. Although trisaccate the species has been placed within a bisaccate genus. By creating a new trisaccate genus the relation with T. crassa would not be clear. Nuskoisporites is limited to monosaccate species; consequently the characteristic shape of the germinal of T. muelleri is absent.

Occurrence: Hengelo Rot salinar and upper Rot pelites; rare. REINHARDT (1964b) mentioned the species from the Lower Rot of Thuringen, Triadispora plicata Klaus 1964 Fig. 22b ; Plate XII, Fig. 4 .

Holotype: Triadispora plicata Klaus 1964, t. 2, f. 15. Remarks and comparisons: Although connected with T. crassa by transitions, we consider forms with a clearly plicate central body and thickened proximal exoexine as T. plicate. Transitions to haploxylonoid forms (T. staplini) and to forms with reduced sacci (T. epigona) have not been demonstrated.

Occurreru:e: Hengelo Rot salinar; rare. KLAUS (1964) reports the species from Italian and French Muschelkalk assemblages; here it is more frequent. Klaus 1964 Fig. 22d; Plate XII, Figs. 5, 6. Holotype: Triadispora epigona Klaus 1964, t. 2, f. 13. Remarks and comparisons: Although connected with T. crassa and T. staplini by transitions, we maintain T. epigona for stratigraphical reasons (p. 326). It differs from the former species by its small reduced sacci. These can be haploxylonoid or faintly diploxylonoid with a semi-lunar shape. But also forms with a small monosaccus are rather frequent. Depending on the saccus shape, the transitions are placed within T. crassa or T. staplini.

Occurrence: Regularly recognized in the Hengelo Rot Group; never in high percentages. KLAUS (1964) Remarks: The author considers the presence or absence of an intexinal tetrad mark within the Striatiti a very important feature. It seems a good argument for subdividing the Striatiti into the Aletestriatiti nov. subinfraturma and the Triletestriatiti nov. subinfraturma (p. 360).

Illinites Kosanke 1950 emend. Klaus 1964 Type species: Illinites unicus Kosanke 1950, t. 1, f. 3. Remarks and comparisons: By restudying the type specimen both JANSONIUS and STAPLIN (1962) and KLAUS (1964) have given valuable contributions to a better knowledge of the genus Illinites (synonym: Complexisporites Jizba 1962). By the proximal exoexinal differentiations (reduced trilete mark accompanied by two laterally placed longitudinal sutures) Illinites can be distinguished from the "Illinites"species from the European Upper Permian (= Eridospollenites Freudenthal 1964, which has to be considered, together with Jugasporites Leschik 1956b , as Limitisporites Leschik 1956b emend. Potonie 1958 (the genus Jugasporites Leschik 1956b emend. Klaus 1963a might be preferable, but according to Art. 57 of the International Code of Botanical Nomenclature Potonie's "choice must be followed"). An intexinal (reduced) trilete or monolete is absent.

Illinites differs from Angustisulcites Freudenthal 1964 emend. by possessing approx. haploxylonoid sacci and by the still proximal, not equatorially placed longitudinal sutures. Both genera are related more to the Striatiti Pant 1954 than to the Disaccitriletes Leschik 1956. So we place both genera in the former infraturma.

Illinites trivisus n. sp. Trilete mark in proximal exoexine well developed: two rays extend to the equator, the third -transversal -ray is hardly reduced. This V-mark is accompanied by two still proximally situated longitudinal sutures. Proximal intexine without (reduced) trilete or monolete mark. Sacci finely infrareticulate, approx. haploxylonoid with narrow equatorial interconnections. Bladder bases usually accompanied by folds. Known size range 70-80 ft (holotype 78 ft).

Comparison: Illinites kosankei Klaus 1964 , also from Upper Bunter assemblages, differs by possessing a strongly reduced Y-mark and by its bigger size. Angustisulcites Freudenthal 1964 emend. Type species: Angustisulcites klausii Freudenthal 1964, t . 2, f. 6a, 6b; Plate XV, fig. 4 . Diagnosis: Pollen bisaccate, striate. Equator of central body approx. circular to transversely elliptical or, very often, subangular (rhombic). Proximally thickened exoexine with V-mark; two rays extend to the equator, the third may be strongly reduced and assymmetrically placed. Apart from the Y-mark there are two equatorially situated longitudinal exoexinal sutures. Consequently these arc only visible in equatorial view (lateral view). Proximal intexine without (reduced) trilete or monolete mark. Sacci faintly diploxylonoid to strongly libelloid. In principle the distal germinal area is biconvex; it is often accompanied by transversal compression folds. (1964) based his generic diagnosis on a badly preserved type specimen which does not show a distinct V-mark in the proximal exoexine. We reprepared the genotype and have been able to demonstrate the V-mark. Specimens without a distinct open mark have also been found in our preparations, but usually it becomes visible with high magnification. In order to include more species we changed Freudenthal's generic description in a more extensive sense; not even to Angustisulcites klausii Freudenthal 1964 can the "narrow deep sulcus" be considered characteristic. Angustisulcites is highly related to Illinites Kosanke emend. Klaus 1964;  it differs by the diploxylonoid shape, but especially by the equatorial position of the lateral sutures, which are invisible in polar view (proximo-distal view). Angustisulcites differs from Lueckisporites Potonie and Klaus 1954 emend. Klaus 1963a by the trilete shape of the proximal exoexina1 mark and by the absence of a monolete or (reduced) trilete mark in the proximal intexine. The latter fact has been the argument for placing Angustisulcites, together with Illinites, within the Aletestriatiti nov. subinfraturma. Freudenthal 1964 Fig. 24a ; Plate XV, Figs. 1, 2, 3A , B, 4.

Holotype: Angustisulcites klausii Freudenthal 1964, t. 2, f. 6a, 6b; Plate XV, Fig. 4. Diagnosis: Pollen bisaccate, striate. Equator of central body circular, transversely elliptical or sub angular (rhombic). Strongly thickened proximal exoexine (3-4.5 fl) with fine infrastructure and trile mark; two rays extend to the equator, the third ray can be strongly reduced and is placed asymmetrically. Equatorially two longitudinal singular exoexinal sutures, only visible in equatorial view. Intexine without (reduced) trilete or monolete mark. Sacci faintly diploxylonoid, distally inclined, laterally close to each other or equatorially interconnected by a narrow exoexinal strip. Distal germinal area fundamentally biconvex; usually accompanied by transversal folds. Observed size range 57-85 fl.

By restudying the holotype we have been able to demonstrate the exoexinal V-mark (p. 355). Although narrow germinal areas appear very frequently, a "narrow deep sulcus" (FREUDENTHAL 1964) cannot be considered characteristic; a variation from 1-7 p, was recognized. A. klausii is very close to Illinites melanocorpus Klaus 1964;  it only differs by its smaller average size (respectively 57-85 p, and 90-120 p,). Further investigations have to show whether 1. melanocorpus can be maintained for stratigraphical reasons. Angustisulcites gorpii n. sp. distinguishes by its libelloid shape, its unreduced transversal trilete ray and by possessing a very characteristic saccus infrareticulum. Angustisulcites grandis (Freudenthal 1964) nov. comb. differs by its striking size.

Occurrence: Regularly recognized in the Rot salinar of Hengelo; low percentages. In the upper part of the overlying Rot pelites, however, A. klausii is the most dominating species.

Angustisulcites grandis (Freudenthal) 1964 nov. comb (Freudenthal 1964) nov. comb.; FREUDENTHAL 1964, t. 5, f. 1. Diagnosis: Pollen bisaccate, striate. Striking but variable size (known size range 110-210 p,). Equator of central body approx. circular to strongly subangular (rhombic). Thickened proximal exoexine with reduced trilete mark; two rays extend to the equator, the third -approx. transversal -is reduced and situated asymmetrically. Equatorially two longitudinal singular exoexinal sutures, only visible in equatorial view. These sutures also limit the thickened proximal exoexine, Proximal intexine without (reduced) trilete or monolete mark. Sacci faintly to strongly diploxylonoid, both proximally and distally inclined, laterally close to each other or equatorially interconnected. Fine, more or less imperfect, saccus-infrareticulum. Distal germinal area fundamentally biconvex, usually accompanied by folds.

Remarks and comparisons: Especially the bigger specimens are usually badly preserved. This also applies to Freudenthal's holotype. Even with high magnification a trilete mark can be suspected only. On account of the general shape and of analogue finds within the variation of a trilete species Freudenthal's specimen has to be maintained as the holotype of Angustisulcites grandis (Freudenthal 1964) nov. comb. Our better preserved specimens explain the upbuilding of A. grandis which differs from Angustisulcites klausii Freudenthal 1964 and Angustisulcites gorpii n. sp. by its striking size.

Occurrence: Regularly recognized in the Hengelo Rot salinar; never in high percentages.

Angustisulcites gorpii n. sp. Diagnosis: Pollen bisaccate, striate. Equator of central body transversely elliptical to subangular (rhombic). Strongly thickened exoexine with trilete mark; two rays always extend to the equator, the third -approx. transversal -ray can also reach the equator or can be slightly reduced; this ray is approx. symmetrically situated. Equatorially two longitudinal singular exoexinal sutures, only visible in equatorial view. The suture situated at the side, to which the transversal trilete ray extends has developed only rudimentalary. Proximal intexine without (reduced) trilete or monolete mark. Sacci libelloid, distally inclined, laterally close to each other. Striking infrareticulum with narrow elongated meshes. Distal germinal area fundamentally biconvex. Known size range 65-95 fJ (holotype 78 fJ).

Remarks and comparisons: Because of the strongly libelloid shape equatorially flattened specimens are very rare; it has been impossible to find a well-preserved specimen that lent itself to illustrate the equatorial sutures. They can often be vaguely observed in approximately polar view. A. gorpii differs from Angustisulcites klausii Freudenthal 1964 and Angustisulcites grandis (Freudenthal 1964) nov. comb. by its welldeveloped transversal trilete ray, the libelloid shape and the characteristic saccus infrareticulum.

Locus typicus: Boring 31, K.N.Z., Hengelo; depth 405.50 m (Rot salinar). Occurrence: Regularly recognized in the Rot salinar of Hengelo; never in high percentages.

Lunatisporites Leschik 1956a emend. Bharadwaj 1962 Type species: Lunatisporites acutus Leschik 1956a, t, 7, f. 24. Remarks and comparisons: By many authors (GREBE 1957; KLAUS 1960; BHARADWA] 1962; ]ANSONIUS 1962; HART 1964; FREUDENTHAL 1964) the type species of Lunatisporites Leschik 1956a and Taeniaesporites Leschik 1956a (respectively Lunatisporites acutus Leschik 1956a and Taeniaesporites kraeuseli Leschik 1956a are considered identical; in this case both genera have to be united. We agree with this conception. However, in the literature there is no unanimity about the question of taxonomical priority, which is given to Lunatisporites as well to Taeniaesporites. LESCHIK (1956a) described both genera in the same paper; Lunatisporites at p. 56, Taeniaesporites at p. 58. The descriptions are poor and insufficient. GREBE (1957) restudied the type species and did not notice any important differences. However, she united both genera with Lueckisporites Potonie & Klaus 1954 . LESCHIK (1959 disagrees with Grebe's concept about the nature of the semi-lunar dark area on the central body of Lunatisporites; this should be a morphological feature instead of an optical effect. KLAUS (1960) followed GREBE (1957) . BHARADWA] (Febr. 1962) states that there are no differences between the two genera. On account of "page priority" he considers Taeniae-sporites a synonym of Lunatisporites Leschik 1956a emend. Bharadwaj 1962 ANSONIUS (April 1962) stated the same concept. But because of the better preserved holotype he gives priority to Taeniaesporites Leschik 1956a emend. ]ansonius 1962 . KLAUS (1963a disagrees, since according to the "page priority" Lunatisporites should have been chosen. He appeals to LESCHIK (1959) in order to maintain a separation between Lunatisporites and Taeniaesporites Leschik 1956a emend. Klaus 1963a . HART (1964 also considers the type species identical, but next he argues inconsistently by maintaining Taeniaesporites without mentioning Lunatispontes as a synonym. The latter genus can be found in the list of synonyms of the genus Protohaploxypinus Samoilovich 1953 emend. Hart 1964 . FREUDENTHAL (1964 follows ]ANSONIUS (1962) . ]ansonius has been perfectly correct and logical in choosing Taeniaesporites. Bharadwaj was guided by the "page priority" when he chose Lunatisporites. On the other hand, this "page priority" has been the very motive of KLAUS (1963a) to separate the genera. However, the idea of "page priority" is not provided by the International Code of Botanical Nomenclature. Art. 51 is very plain when it states: " ... The author who first unites taxa bearing names or epithets of the same date has the right to choose one of them, and his choice must be followed" .

Bharadwaj did not make use of "the right to choose one of them", but yet "his choice must be followed". Lunatisporites is restricted to forms without a monolete or reduced trilete mark in the proximal intexine of the central body. As for the existence of these characteristics we refer to the description of Taeniaepollenites n. gen. (remarks, p. 360) . Lunatisporites differs from Protohaploxypinus Samoilovich 1953 emend. Hart 1964 and Striatopodocarpites Sedova 1956 emend. Bharadwaj 1962 by the presence of a biconvex germinal area and narrow equatorial bladder connections.

Lunatisporites puntii n. sp. Diagnosis: Pollen bisaccate, striate. Equator of central body approx. circular to transversely elliptical or subangular (rhombic). Thickened proximal cxoexine with 4-6 taeniae in polar view, frequently of unequal width, usually separated by very narrow sutures. Taeniae with fine infrastructure. Proximal intcxine without tetrad mark. Sacci more or less diploxylonoid to platysaccoid, distally inclined, laterally very close to each other or even equatorially interconnected. Sacci very finely infrareticulate. Distal germinal area in principle biconvex, frequently accompanied by transversal compression folds. Known size range 79-119 fl (holotype 115 fl).

Remarks and comparisons: Within the variation of the species the shape of the sacci is liable to rather important divergences. Specimens with sutures between the taeniae -a characteristic of Taeniaepollenites n. gen. -are uncommon. A few specimens with remarkably deformed taeniae have been found (Plate XIV, Fig. 4 ). L. puntii differs from Lunatisporites acutus Leschik 1956a especially by its bigger size. Striatoabietites Sedova 1956 emend. Hart 1964 Type species: Strirtoabietites bricki Sedova 1964, t. 41, f. 5. Comparison: Striatoabietites differs from Tubantiapollenites n. gen. by the absence of a reduced trilete (roof-shaped) or monolete (straight) mark in the proximal intexine. Striatoabietites aytugii n. sp. Remarks and comparisons: Usually the shape is faintly diploxylonoid but occasionally it may become more pronounced. S. aytugii differs from T ubantiapollenites balmei (Klaus 1964) nov. comb. by the absence of a (reduced) trilete or monolete mark in the proximal intexine. Diagnosis: See diagnosis of Taeniaesporites Leschik 1956a emend. KLAUS 1963a (KLAUS 1963a . This excellent diagnosis can serve without restrictions as a description of a new striate genus, which includes among others all the forms recognized by KLAUS (1963a). Since species of Taeniaepollenites n. gen. were mostly placed within the genus Taeniaesporites Leschik 1956a and since the latter genus has to be considered a synonym of Lunatisporites Leschik 1956a emend Bharadwaj 1962 , it seems useful to check the concepts about the intexinal V-mark within these genera. LESCHIK (1956a) creates both Lunatisporites and Taeniaesporites, not mentioning the existence of an V-mark. Also the illustrations do not show a tetrad mark. However, the genera are placed within the Disacciatriletes.

LESCHIK (1956b) also describes Taeniaesporites noviaulensis from the German Zechstein deposits. A monolete mark is clearly visible and is mentioned in the description. GREBE (1957) In principle POTONIE (1958) follows GREBE (1957) ; however, he maintains the species "Lueckisporites" noviaulensis; nothing is to be said about the monolete mark. Lunatisporites remains separate; like Grebe, Potonie has restudied the type species but an Y-mark was not demonstrated. Various authors (e.g. LAKHANPAL, SAH and DUBE 1960; POTONIE and LELE 1961) continued to interpret Lunatisporites in this way. LESCHIK (1959) points out the differences between his alete Triassic species and his Permian T. noviaulensis. KLAUS (1960) follows GREBE (1957); he finds "Lueckisporites kraeuseli" in Keuper sediments; pollen without V-mark.

BHARADWA] (1962) considers Taeniaesporites a synonym of Lunatisporites Leschik 1956a emend. Bharadwaj 1962, which does not possess a tetrad mark. In India this concept is commonly followed.

We agree with it too (compare p. 357).

] ANSONIUS (1962) emends the generic diagnosis of Taeniaesporites and also describes some new species. Nothing is stated about a possible tetrad mark. There is a strong resemblance with European monolete species. Particularly Taeniaesporites novimundi ]ansonius 1962 reminds us of T. noviaulensis. However, studying some of ]ansonius' slides we have not been able to recognize a convincing tetrad mark within the Canadian species. Yet they differ from Lunatisporites Leschik 1956a emend. Bharadwaj 1962 ORLOWSKA ZWOLINSKA (1962) determines T. noviaulensis from the Polish Upper Permian deposits; she mentions the monolete mark. GREBE and SCHWEITZER (1962) do not pay attention to the monolete mark of Lueckisporites noviaulensis (Leschik 1956a ) Potonie 1958 . BALME (1963 follows ]ANSONIUS (1962) but he mentions the monolete marks both of ef. T. noviaulensis and Taeniaesporites obex Balme 1963 . In his illustrations the marks are well visible. SCHAARSCHMIDT (1963a) considers Taeniaesporites a synonym of Striatites Pant 1955. Some species, like Striatites noviaulensis (Leschik 1956a ) Schaarschmidt 1693, may possess a proximal monolete mark.

By emending Taeniaesporites, KLAUS (1963a) gives an excellent diagnosis for the monolete forms. In fact all his new species are monolete. So they must be compared with T. nooiaulensis instead of with T. kraeuseli, the type species of the genus.

A clear intexine-mark is also visible in the illustrations of T. noviaulensis from the Zechstein of Thuringen (ULLRICH 1964) .

In his generic descriptions of striate pollen HART (1964) does not reckon with possible tetrad marks. With regard to Taeniaesporites he follows ]ansonius' emendation. He considers the mark of T. obex a species-characteristic, suppressing it, however, when describing T. noviaulensis (syn: T. novimundi). (1964) also recognize Lunatisporites acutus Leschik 1956a in the Austrian Upper Triassic. They do not mention the presence of a tetrad mark. Within European Bunter and Muschelkalk sediments KLAUS (1964) recognizes T. novimundi. Not mentioning the tetrad mark, he classes this species together with the monolete Taeniaesporites austriacus Klaus 1964 , under the Disaccimonoletes Klaus 1963a . This infraturma is considered to contain bisaccate mono1ete pollen but, however, it excludes striate pollen.

In FREUDENTHAL'S (1964) opinion the specimens from the Dutch Bunter belong to T. noviaulensis (syn: T. novimundi). The tetrad mark is visible in his illustrations but it is not drawn into the discussion. Also SCHULZ (1964) compares his specimen from the Middle Bunter with noviaulensis; nothing is stated about a possible monolete mark.

According to this enumeration it is clear that there is no unanimity about the importance of the presence or absence of a monolete tetrad mark. This should be regarded a grave hiatus, particularly because within the Hengelo assemblage we recognize both forms habitu Lunatisporites Leschik 1956a emend Bharadwaj 1962, without a tetrad mark, and forms habitu Taeniaesporites Leschik 1956a emend. Klaus 1963a with well-developed monolete or reduced trilete marks. So we want to separate them strictly.

The genus Taeniaesporites cannot be maintained because it is a synonym of Lunatisporites (compare p. 358; also in the case ofseparating these genera one has to realize that the type species of Taeniaesporites does not possess a tetrad mark). So the genus Taeniaepollenites n. gen. is proposed, including species with monolete or reduced trilete marks. Choosing this related name may cause confusion, but we want to keep the prefix Taeniae-. Remarks and comparisons: In principle there are 2 polar taeniae but these can be divided. Specimens with 3 or 4 polar taeniae are very frequent and even specimens with 2t or 3t taeniae are common.

T. jonkeri differs from Taeniaepollenites multiplex n. sp. and Taeniaepollenites discrepans n. sp. by its haploxylonoid shape. Taeniaepollenites hengeloensis n. sp. possesses reduced sacci. These newly described species differ from the Taeniaepollenites-species from European Upper Permian assemblages (=" Taeniaesporites" with proximal intexinemark; compare p. 360) by their relatively finer saccus-infrareticulum. Diagnosis: Pollen bisaccate, striate. Equator of the central body approx. circular to longitudinally elliptical. Thickened proximal exoexine, differentiated into 2 equatorial taeniae and 2-4 polar taeniae. The taeniae are separated by rather wide sutures; they are pronounced infragranulate, frequently the margins are more or less crenulate. Proximal intexine with reduced trilete to monolete mark. Sacci faintly to strongly diploxylonoid, strongly distally inclined; meshes of saccus-infrareticulum 1-3 fl wide. Wide distal germinal area with approx. structureless exine. Known size range 80-105 fl (holotype 84 fl).

Remarks and comparisons: Specimens with 2, 2t, 3, 3!, and 4 polar taeniae were recognized (compare T. jonkeri, remarks above). The appearance of an elliptical equator is mostly attended with a more pronounced diploxylonoid shape. There are, however, progressive transitions to faintly diploxylonoid forms with a circular equator. So a separation seems undesirable. T. multiplex differs from Taeniaepollenites discrepans n. sp. by its thickened proximal exoexine with pronounced infragranulate taeniae. The species differs from Taeniaepollenites jonkeri n. sp. and Taeniaepollenites hengeloensis n. sp. by its diploxylonoid shape.

Locus typicus: Boring 31, K.N.Z., Hengelo; depth 405.50 m (Rot salinar). Occurrence: Most common striate species in the Hengelo Rot salinar but never reaching high percentages. Also recognized in the overlying Rot pelites.

Taeniaepollenites discrepans n. sp. Diagnosis: Pollen bisaccate, striate. Equator of the central body approx. circular to longitudinally elliptical. Hardly thickened proximal exoexine differentiated into 2 equatorial taeniae and 2-5 polar taeniae. The taeniae are separated by rather wide sutures; they are faintly infrastructured. Proximal intexine with reduced trilete to monolete mark. Sacci diploxylonoid, distally inclined; meshes of saccus-infrareticulum 1-2 Il wide. Wide distal germinal area with approx. structureless exine. Known size range 90-100 Il (holotype 981l).

Remarks and comparisons: In principle there are 2 polar taeniae; they can be split up into more exoexinal strips, which are sometimes incompletely developed (compare T. jonkeri, remarks p. 363). T. discrepans differs from Taeniaepollenites multiplex n. sp. by its hardly thickened proximal exoexine without pronounced infragranulate structure. Taeniaepollenites jonkeri n. sp. and Taeniaepollenites hengeloensis n. sp: are haploxylonoid and possess also a thickened proximal exoexme, Remarks and comparisons: In principle there are 2 polar taeniae; they can be split up into more exoexinal strips which are sometimes incompletely developed (compare T. jonkeri, remarks, p. 363). T. hengeloensis differs from Taeniaepollenites jonkeri n. sp. by its reduced sacci and the circular equator. Taeniaepollenites multiplex n. sp. and Taeniaepollenites discrepans n. sp. are diploxylonoid.

Locus typicus: Boring 31, K.N.Z., Hengelo; depth 404 m (Rot salinar). Occurrence: Rot salinar of Hengelo; very rare.

Tubantiapollenites n. gen.

Type species: Tubantiapollenites striatitoides n. sp., Plate XIX, Fig. 3 . Derioatio nominis: Tubantia, Latin name for Twente, the region from which our samples originate.

Diagnosis: Pollen bisaccate, multistriate. Slightly thickened proximal exoexine differentiated into a great number of taeniae; these are separated by very narrow sutures. Proximal intexine with reduced trilete (roof-shaped) to monolete (straight) mark. Sacci haploxylonoid or faintly diploxylonoid. Wide distal germinal area.

Remarks and comparisons: Except Striatoabietites balmei Klaus 1964 Fig. 3 .

Derivatio nominis: Apart from the tetrad mark, the new species reminds one of Striatites Pant 1955 emend. Klaus 1963a Diagnosis: Pollen bisaccate, multistriate. Equator of the central body approx. circular to subangular. Slightly thickened proximal exoexine differentiated into taeniae (7-10 visible in polar view); taeniae finely infragranulate, separated by very narrow sutures. Proximal intexine with reduced trilete to monolete mark. Small sacci, haploxylonoid, semi-lunar, finely infrareticu1ate. Wide distal germinal area, usually limited by compression folds. Known size range 60-65 f1 (holotype 64 f1).

Remarks and comparisons: Often specimens of T. striatitoides tend to release the sacci. The species differs from Tubantiapollenites schulzii n. sp. by the small haploxylonoid sacci. Tubantiapollenites balmei (Klaus 1964) nov. comb. possesses a longitudinally elliptical equator. Furthermore, compared with the two other species, T. striatitoides possesses a smaller number of taeniae. Tubantiapollenites balmei (Klaus 1964) nov. comb. Fig. 28c ; Plate XIX, Fig. 5 . Holotype: Tubantiapollenites (al. Striatoabietites) balmei (Klaus 1964) nov. comb.; KLAUS 1964, t, 2, f. 17. Remarks and comparisons: On account of the presence of a proximal intexine-mark Klaus' species is considered as Tubantiapollenites n. gen. The length of the roof-shaped or straight mark is rather variable; forms with elongated marks predominate, but there is no reason to propose a separation.

In polar view 13-20 taeniae are visible. Observed size range 40-70 fl. The longitudinally elliptical equator of the central body is characteristic; by this feature T. balmei can be distinguished from Tubantiapollenites schulzii n. sp. and Tubaniiapollemtes striatitoides n. sp.; Moreover, the latter species is haploxylonoid.

Occurrence: Rot salinar of Hengelo; rare. KLAUS (1964) Diagnosis: Pollen bisaccate, multistriate. Equator of central body approx. circular. Slightly thickened proximal exoexine differentiated into taeniae (10-15 fl visible in polar view); taeniae finely infragranulate, separated by very narrow sutures. Proximal intexine with reduced trilete or monolete mark. Sacci diploxylonoid, finely infrareticulate. Wide distal germinal area. Known size range 46-56 fl (holotype 51 fl).

Often the intexinal mark of T. schulrii is hardly visible. Protosacculina jansonii Freudenthal 1964 may be considered conspecific with this species; we restudied the holotype but could not demonstrate the intexinal mark with certainty. To propose a new combination seems incorrect, because in that case" Tubantiapollenites jansonii" should be based on a holotype without the characteristic tetrad mark. T. schulzii differs from Tubantiapollenites balmei (Klaus 1964) nov. comb. by its circular equator. Tubantiapollenites striatitoides n. sp. possesses small haploxylonoid sacci and a smaller number of taeniae. Remarks and comparisons: A generic differentiation of monocolpate pollen grains is hampered by the few characteristics which can be used in describing the species; this is due to the relatively simple shape. So provisionally it seems more reasonable to use the genus Cycadopites in a very broad sense (compare e.g. jANSONIUS 1962). Even the relation with Monosulcites (Cookson 1947) ex Couper 1953 is not clear; within the variation of a species both Cycadopites-like specimens and forms corresponding to the description of Monosulcites are found.

Cycadopites com n. sp. Diagnosis: Pollen monocolpate with approx. elliptical outline. Thin exine with fine infrastructure. Sulcus lemniscatoid to irregularly elliptical depending on the fossilisation. Size very constant (28-31 ft).

Remarks and comparisons: Many specimens show a wide sulcus, which is not lemniscatoid; these forms should have been considered as Monosulcites Cookson 1947 ex Couper 1953 . However, they can be derived from true lemniscatoid Cycadopites forms by progressive transitions.

C. coxii differs from Cycadopites sujJlavus n. sp. by its smaller size; the size range of the latter species is also very constant (42-45 ft); transitions were not recognized, so a separation of the species seems justified. Diagnosis: Pollen monocolpate with approx. elliptical outline. Thin exine with fine infrastructure. In principle the sulcus possesses a lemniscatoid shape, but elongated elliptical outlines appear frequently. Size very constant (42-45 ft).

Remarks and comparisons: Within the variation of C. sujJlavus occur Monosulcites-like forms (compare C. coxii; remarks p. 367). C. sujJlavus is very related to Cycadopites coxii n. sp., but the absence of transitional sizes justifies a separation. Cycadopites trusheimii n. sp. differs by its bigger size and its characteristic folding. 

Diagnosis: Pollen monocolpate with approx. elliptical outline. Thin exine with fine infrastructure. Sulcus usually lemniscatoid to elongated elliptical. Parallel to sulcus a varying number of narrow folds. Size very constant (54-58 f-l).

Remarks and comparisons: We consider the presence of the narrow folds an important characteristic; within the variation of Cycadopites coxii n. sp. and Cycadopites sufflauus n. sp. this type of folding never appears. Diagnosis: Pollen monocolpatc with irregular elliptical outline. Thin exine with rather pronounced infragranulate structure. Wide sulcus with crenulate margin. Small sizes, very constant (18-21 f-l).

Remarks and comparisons: A lemniscatoid sulcus has never been recognized; so the species might belong to Monosulcites Cookson 1947 ex Couper 1953 . However, the relations between Cycadopites and Monosulcites are not very clear to us (p. 367). It seems therefore preferable to consider the species as Cycadopites. It differs from Cycadopites coxii n. sp., Cycadopites sufflaous n. sp. and Cycadopites trusheimii n. sp. by its very small size, its crenulate sulcus margin and a more pronounced infrastructure.

Locus typicus: Boring 31, K.N.Z., Hengelo; depth 411.50 m (Rot salinar), Occurrence: Regularly recognized in the Rot salinar of Hengelo; low percentages.

A few specimens of rather particular plant microfossils were found in the palynological assemblage of Hengelo (Plate XX, Fig. 6 ). These bodies consist of some twisted strips of a material remarkably resembling the infrareticulate saccus exine of saccate pollen. Size approx. 80 f-l.

British Permian saccate and monosulcate miospores

Zur Einstufung alpiner Salztone mittels Sporen

Die geologische Verbreitung von Sporen und Pollen in der deutschen Trias

Zur Kenntnis der Sporae dispersae des mitteldeutschen

Sporae dispersae aus der Trias von

Etude des microspores du Namurien aTarla-Agzi (Bassin houiller d'Amasra, Turquie)

Description de quelques microspores du Permo-Carbonifere francais

Diagnose des pollens de Pinus silvestriset Pinus uncinata des Pyrenees

Palynological evidence bearing on the Permian-Carboniferous boundary in Western Australia (abstract only)

Bot. 3: 89-98. and . 1956. Monolete, monocolpate and alete sporomorphs from Australian Permian sediments

Trilete sporomorphs from Australian Permian sediments

Palynology and stratigraphy of Upper Paleozoic sediments of the Maritime Provinces, Canada (abstract only)

On the occurrence of spores in the Carboniferous formation of Scotland

Sporological study of seam VIII in Raniganj coalfield, Bihar (India) -part I description of sporae dispersae

The geology of the Vinccntinian Alps

Gymnospermous pollen from some Permian and Mesozoic sediments in the United States (abstract only)

Description of nine species of small spores from the British coal measures

Early Devonian spores from a borehole in southern England

Fossil microflora from the Mohgoan Kalan beds of the Madhya Pradesh

Some trilete spores from Upper Mesozoic deposits in the Eastern Australian region

Classification des spores et des pollens du Carbonifere au Lias

British mesozoic microspores and pollen grains, a systematic and stratigraphic study

Perinian sporomorphs associated with fossil plants and fusulinids from Apillapampa, Bolivia (abstract only)

The production of salt in the Netherlands

Etude palynologique d'une argile provenant de la limite Lias-Dogger, dans un sondage a

The Upper Triassic flora of Arizona

Experimentelle palynologische Untersuchung des Gipses aus dem Mecsekgebirge, Sudungarn

Les spores et grains de pollen du Wealdien du Hainaut

Microspores of the Upper Silesian coal measures (in Polish and Czech; Latin descriptions)

On the occurrence of tetrads and dyads

Suggestions for the classifications of fossil and recent pollen grains and spores

Geology of the Netherlands IV (in Dutch)

Palynology of Lower Triassic rock salt

Die sporae dispersae des niederrheinischen

A review of Mesozoic geological history in the Netherlands

Stratigraphy and palynology of the Upper Carboniferous coal measures in the Cumberland Basin of Nova Scotia

Zur Kenntnis der mesozoischen Equisetales Schwedens

-1956b. Description of some genera and species of fossil pollen and spores

A review of the classification and distribution of the Permian miospore: Disaccate Striatiti

Spores and pollen from a Permian-Triassic transition

The Glossopteris flora of the Belgian Congo

Geologic range of Paleozoic spores in

Palynological reconnaissance of the Lower Carboniferous of Spitsbergen

Sporenformen des Aegirhorizonts des Ruhr-Reviers, Wurzburg

Sporae dispersae des Kaipingbeckens, ihre palaontologische und stratigraphische Bearbeitung im Hinblick auf eine Parallelisierung mit dem Ruhrkarbon und dem Pennsylvanian von Illinois

Neuere Forschungen tiber die Microflora des polnischen Karbon

Late Paleozoic saccate pollen, structure and relationship (abstract only)

Reconnaissance palynologique du Permien, Trias et ]urassique des sondages effectues par la

Triassic spores and pollen grains from the Ipswich coalfield

Late Paleozoic bisaccate pollen from the United States Midcontinent area

Some Lower Mesophytic microspores of Europe with remarks on their relation to the Gondwana-microflora

The spores of Lycopodium, Phylloglossum, Selaginella and Isoetes, and their value in the study of microfossils of Paleozoic age

Pennsylvanian spores of Illinois and their use in correlation

Uber einige liassische "angiospermide

Further observations on plant microfossils from a carbonaceous shale (Krols) near Naini Tal

Die Keuperflora von Neuewelt bei Basel

Etude de la microflore infraliassique d'un sondage effectue dans Ie sous-sol de

Etude de la microflore bajocienne d'un sondage effectue dans le sous-sol de

Sporenformen aus dem Floz Bismarck des Ruhrgebietes

Atlas of the spores and pollen of the Paleozoic deposits of Kazakhstan (in Russian)

Contribution to the geological history of the Hepaticae

0n Riccisporites tuberculatus and its occurrence in certain strata of the

Identification of spores and pollen of the Jurassic and Cretaceous (in Russian)

On the genus Pityosporites Seward 1914 with a new description of Pityosporites antarcticus Seward

Microfossils from a carbonaceous shale from the Dali Beds of South Rewa Gondwana Basin

Paleobotanical examinations of Cretaceous and Tertiary coals

Sur la position stratigraphique de I'Autunien et de ses analogues

Pleuromeia corda from the Lower Triassic sediments of the Russian platform

The stratigraphic significance of the small spore assemblage of the La Camocha mine

Uber das Vorkommen eines mesozoischen Sapropelgesteins in Schonen

A first finding of Zechstein sporomorphs in Poland (in Polish; English summary)

The microspore assemblage from the Lungtan series of Changhsing, Chekiang. (in Chinese; English summary)

Geological History of the Netherlands. The Hague

Suggestions for the classification and nomenclature of fossil spores and pollen grains

Keuper sporomorphs from Swierczyna

Spores in strata of Late Pennsylvanian cyclothems in the Illinois Basin

Zur Entstehung und Entwicklung des Angiospermiden Pollens in der Erdgeschichte

Observations sur le palynologie du Westphalien B et C de la parte occidentale du Massif du Borinage

Lycospora Schopf, Wilson & Bentall. C.R. 5e Congr

Lower Carboniferous microfloras of Spitsbergen

Similarities between Lower Carboniferous microfloras of Spitsbergen

Die Flora des Rotliegendes von Thuringen

Zur Mikroskopie der Braunkohlen I

Die Phylogenese der Sporengestalt beim Gang durch die fossi1en Pflanzenfamilien (ohne die Angiospermen)

Die Gattungen der palaeozoischen Sporae dispersae und ihre Stratigraphie

Die Sporae dispersae des Ruhrkarbons III

Studies in the Talchir flora of India. 1, Sporae dispersae from the Talchir beds of South Rewa Gondwana Basin

Pollen morphology of the Euphorbiaceae with special reference to taxonomy

Uber die Sporae dispersae der Thuringer Trias

Neue Untersuchungen iiber die Mikrostruktur der Steinkoh1e des Carbons

Monosaccate Pteridospermenpollen aus dem Karbon und Perm sowie eine allgemeine Betrachtung der palaozoischen Pollen mit Luftsack

Stratigraphical distribution of some Devonian and Lower Carboniferous spores. C.R. 5e Congr

Spores and pollen from Permian deposits of the Cherdyn and Aktyubinsk areas, Cis-Urals. Translation of the Russian text in: Oklahoma Geol

Ober den Wandel der Sporenflora im deutschen Perm

Die Ka1i und Steinsalzlagerstatten des Zechsteins in der Deutschen Demokratischen Repub1ik

An annotated synopsis of Paleozoic fossil spores and the definition of generic groups

Sporenpalaontologische Untersuchungen zur Rhat-Lias-Grenze in Thiiringen und der A1tmark

Four new genera and type species

Schiittungsrichtungen und Minera1-Provinzen im westdeutschen Buntsandstein

A miospore assemblage from the Permian oflraq

In: DORST, J. C. et at. Evolution, the present state of the problem (Symposium "Evolution

Verrucosisporites (Ibrahim) emend. 5e Congo Int

The fossil flora of the Jabapur series. 3, Spores and pollen grains

Miospores from the Lower Limestone shales (Tournaisian) of the Forest of Dean Basin, Gloucestershire. C.R. 5e Congr

Contribution a la connaissance de la microflore du Trias (abstract only)

On some disaccate pollen grains of Permian to Middle Jurassic age

Zur Stratigraphie und Palaontologie der marin beeinflussten Randfazies des Zechsteinbeckens in Ostthiiringen und Sachsen. Freib. Forsch

Sporological study of the coals from Falkenberg (Faalquemont) Colliery, Lotharingen (Lorrain)

Die Sporen und Pollen der Aachener Kreide und ihre Bedeutung fiir die Charakterisierung des Mittleren Senons

Pennsylvanian plant microfossils of the Croweburg coal in Oklahoma

Tertiary pollen. 2: The oil shales of the Eocene Green River formation

Spore-pollen complexes from Upper Permian deposits from some localities in North European Russia (in Russian)

Without the help of Mr. J. van der Burgh, and Mr. F. de Vries it might have been impossible to illustrate this publication with microphotographs. Staff-members and fellow-students at the Palaeobotanical and Pollenmorphological laboratories have aided substantially by giving useful suggestions and by their personal interest in this investigation. Mr. P. van den Kruk read the manuscript and corrected the English text; his engaging criticism has been highly appreciated.Thanks are especially due to the Koninklijke Nederlandsche Zoutindustrie for supplying the requisite rock samples.

Some important papers on Permian and Triassic palynology became available to us after finishing the present investigation 1).We regret the fact of being unable to make use of the information derived from them. Apart from some inevitable synonyms these papers give further information about the horizontal and vertical distribution of Lower Mesophytic pollen and spores in Europe.MADLER (1964) has described palynological assemblages from the Rot, Lower Muschelkalk and Keuper of Germany. Other data from the Rot is given by SCHULZ (1965) and by REINHARDT and SCHMITZ (1965) . An important stratigraphic diagram is published by KLAUS (1965) . Finally, I ought to mention two papers by CLARKE (1965a, b) on Keuper and Permian palynology, respectively.