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Montreal : PRINTED BY JOHN LOVELL, ST. NICHOLAS STREET. 1869. H^'i NOTICE. In the preface to Decade III., already published, the reason has been given why the present one, though second in time, is first in number. In the same preface it has been stated that the present Decade, confided for the descriptions to Mr. J. W. Salter, palaeon- tologist to the Geological Survey of the United Kingdom, is intended to illustrate a commingling of forms heretofore supposed to belong to distinct epochs; that the drawings are by Mr. Bone, and the engravings by Mr. Sowerby, artists well known for their accuracy and skill. W. E. LOGAN. MoNTKKAL, llth April, 1859. 165537 PREEACE. In describing the few generic types given in these pages, I am acting as pioneer for my friend Mr. E. Billings, who wishes me to share this portion of his task, and I very willingly join with him, and with Professor James Hall, in commencing this series of Decades. The drawings and plates have been executed for some time past. In a short memoir on the fossils collected in the limestone at Pauquette's Rapids, on the Ottawa River, which was presented to the British Association in the year 1851, and appended to Sir William Logan's paper on the Rocks of Canada, it was stated, that the lime- stone included fossils characteristic of all the lower divisions of the New York system, from the Calciferous sandrock to the Trenton lime- stone inclusive. With regard to the lowest of these strata, a r ' ; faction may be made, for, when more closely examined, the Emm'^halus uniangulatus of that rock appears to be somewhat different from the Ottawa shell referred to it. The other limestones are certainly represented ; — the Chazy by the peculiar genus Maclurea, and the Birdseye and Black-river limestones by some identical corals and shells. With the Trenton formation, as might be expected, the affinity is greatest ; and the beautifully preserved fossils, silicified in a pure calcareous matrix, and weathered extensively, permit of accurate comparison with the figures and descriptions of those from the United States. In this collection from a single calcareous band, we meet with the Belleroplion stdcatinus and B. rotundatus of the Chazy limestone ; Murchisonia ventricosa and the Stromatocerium from the Birdseye. VI. PREFACE, There are Black-river limestone species, viz., Columnaria alvcolata, and the remarkable cephalopod, Gonioceras anccps, of Hall. Of Trenton species, we have in abundance the Stroyhomena filitexta, Pentamcrus {atrypa) hemiplicatiis and Atrypa incrcbcscms, Murchisonia gracilis and M. bicincta, Cyrtoceras annulatum and C.lamcUosum omnW (C. Billingsii of this Decade), Orthoceras arcnoliratum, hilineatum and laqueatum of Hall, together with Ormoceras tenuijilum, a fossil common to both the Trenton and Black-river limestones. Schizocrimis nodosus is the common Crinoid, and species of Petraia {Strqtelasma), with Favosites hjcoperdofi, go to swell the list of Trenton spe ■^ies. Lastly, there is the characteristic Asajihus gigas, so that the parallel is complete. J. W. SALTER. CANADIAN ORGANIC REMAINS. Maclurea Logani, Salter. Decade I. Plate I. Generic character. — Maclurea, Lesueur. Mollusca Nucleobranchiata. Family Atlantidae? "Shell discoidal, few whorled, reversed* (the apical whorls being brought down to the base and the umbilicus flattened out) ; upper surface convex, deeply perfo- rate instead of raised into a spire ; outer side spirally grooved ; operculum sinistrally sub-spiral, solid, with two internal pro- jections for the attachment of muscles — one of them beneath the nucleus, and very thick and rugose." — ^Woodward. Synonyms. — M. Logani, Salter, in Eep. Brit. Assoc, 1851, Trans. Sections, page 63 ; in Murchison's " Siluria," 3rd edit., 1859, page 215, figure 1 (?) and ]a, operculum. Diagnosis. — M. 3 J uncias lata,, paiicispirata ; anfractihns 4-5 (ultimo in latitudine prceccdentem tcr superante), suhtus planisshnis lavigatis, et ad latcra multistriatis insuper, valde convexis, umbilico parvo. This fine species, detected in great plenty by the officers of the Survey in exploring the Ottawa river, was first noticed in Sir R. I. Murchison's paper on the Silurian Rocks of the South-west of Scot- land, in the Quarterly Journal of the Geological Society, vol. vii., 1851, page 176, and its name proposed in the British Association Reports for the same year. * The reader will please to bear in mind, that though drawn uppermost on the plate (a position which shews the characters best), the flat spiral side of the whorls is really to be considered the base, and the umbilicus the upper side. See Woodward's Manual of Shells, p. 202, where the shell is represented (tig. 106) in its normal position. CANADIAN FOSSILS. It is clearly distinct from, though closely allied to, the great Maclurca magna of the Chazy limestone, which may be seen so often in the paving-slabs and door-ways of New York, and which has been well figured by James Hall. The germs is by no means rare in the old deposits of the Silurian seas, and apparently there were several very distinct species, some of which are yet unpublished, and one, M. Peachii (Suiter), which has the operculum extravagantly elongated and curved, occurs in plenty in a rock very like the Canadian limestone, and full of similar types, in the north-west angle of Scotland. It has been figured, and its locality described, by Sir R. I. Murchison, in the Quarterly Journal Geological Society for 1858. Another is plentiful in the Llandeilo limestones of the south of Scotland. Descrij)tiofi. — M. Logani, when perfect, is fully three and a half inches wide, and is conspicuous for the great flatness of its lower or whorled side, and the fewness of its whorls, for, if we except one or two minute inner ones, there are but two or three distinct whorls, which diminish so rapidly in breadth that the outer is at least thrice the width of the preceding ones in succession, and greater than that of all the inner whorls taken collectively : in M. magna it is greatly less than these. The whorls are very gently convex between the sutures, which are sharply marked though not deep, and are closely striated by regular sharp-arched lines of growth. The sides of the whorl are steep, pyramidal, the depth exceeding the width of the whorl, and are furrowed by a number of deep grooves, sometimes 16 or 17, a few of which are interlined with smaller ones. Occa- sionally seven or eight only are present, or a deep one (figure 3) occurs at a short interval ; but this may be the result of injury. The base itself is smooth, or with faint concentric strias only, and the umbilicus* rather abrupt and very narrow, not above one third the width of the whorl, and with a rounded edge. The shell is solid, nearly a line thick. The most singular part of the shell is its operculum, sometimes fixed, as in figure 3, in its normal position, at other times drawn within the shell. It is exceedingly solid, the successive layers are subspirally arranged, tiling over one another, and are antiquated in growth. The nucleus is near the inner and lower angle of the mouth ; in old shells it is pushed further out, and becomes the apex of a very solid short cone, one face of which lies close upon the inner flat * Used in a false sense, since it is the perforate spire. CANADFAN FOSSILS. surface of the whorl. Two curved furrows radiati'i-r from the nucleus divide the surface into three arcie, less distinct in the mature shell. Inside, a thick, compressed process (a) takes its rise beneath the nucleus, retaining its place near the inner angle of the mouth, even in the adult shell, when the nucleus itself has removed further out (figure ()). The process is as broad as long, and on its oblique free margin it is roughened and grooved for the attachment of muscles. Another attachment, similar but much less prominent, exists at the inner and upper angle (0), and a line of minute prominences partially connects the two. These processes have their analogues in the internal ridges of the operculum in Nirifa and some other genera, and in that of the small Pteropod shell, McGUlkraijia (Forbes), but no recent shells are known in which they are equally produced. The view above expressed of the shell being a reversed one in which the spire is deeply sunk, in the so-called umbilicus, and the latter expanded and flattened so as to appear like the upper side in ordinary shells, will not appear unlikely, if comparison be made with Oj)kilcia (plate 3), in which there is a similar condition of the spire. Moreover, this view has the advantage of rendering it unnecessary to suppose an operculum arranged on a different plan to that of ordinary univalves, since no case is known in which the nucleus is placed at the upper angle of the mouth, though some few have it external. The genus Atalan/a however, says AI. Woodward, has the spire and the operculum both sinistral ; hence it is possible that Muclurca might be an opposite case, in which it is dextral in both. The alliance of this heavy shell with the lighter and fragile Nucleobranchs would seem much more unlikely, had we not such solid forms as Betkrophoti to compare it with. But there are no other genera with which it can be better associated, since Etmnpha- lus has quite a different operculum (nmltispiral), and no opercula are known in Ophikta or Raphistoma, depressed forms resembling Madima, but which are probably, with Murchisonia, members of the families lanthinidaj or Trochidfe (sec plates 2, 3). Prof. Forbes believed there was some affinity between Muclurca arid McGUliiraijia, above men- tioned, a minute spiral Pteropod with the nucleus of the operculum external, and with a process beneath it. But this affinity is not so close as that suggested by BcUerophon with tlie Nucleobranchs, and we nmst therefore leave it for the present where the judgment of Mr. Woodward has placed it, and regard Madurea as a Heteropod with a heavy shell, and probably stationary or nearly so on the bottom, seeing that its 10 CANADIAN FOSSILS. upper or convex side is constantly overgrown with sponge (Stromato- ccrium rugosum*), while the flat or lower side preserves the sharp lines of growth, which would have been abraded had the animal been endowed with much locomotion. Raphistoma, Helicotoma, and Opiiileta. Decade I. Plates II. and III. Genus Scalitcs, Conrad. Mollusca Gasteropoda. Family lanthinidcC. Shell thin, turbinate or depressed, with angular whorls, flat above ; aperture deeply notched, but without a band. Sub-genus Scalitcs. Turbinate; whorls flat above, turrited, pro- duced below ; umbilicus none. Form elongate. Sub-genus Raphistoma, Hall. Depressed, often discoid ; spire flat, or only gently convex, with close sutures ; whorls acute angu- lar externally, and often with an angular edge to the moderate umbilicus. Form lenticular. Sub-genus Hd'icotoma, Salter. Depressed, discoid ; spire nearly flat ; whorls obtusely angular externally, rounded below ; umbilicus broad. Form cirrlioid or helicoid. Sub-genus Oph'dcta, Vanuxem. Discoidal ; spire sunk above ; umbilicus below perfectly open, and exposing the whorls all on one plane; whorls numerous, truncate and biangular exteriorly; mouth trigonal. Forms with deeply concave spires. On mature consideration I cannot find any reason for separating the above series of forms, except as sub-genera. They pass into each other by almost insensible degrees, some species of Ilcrphistornn, for instance, being merely depressed Scallfcs, while others need but a little more angularity below to bet^ome species of OphUcki. Helicotoma is a new sub-generic form, which I have been obliged to institute in order to express a middle term of the series, one in wliich the true discoid form of Ra phi si msj a more elongate species. Our specimens may however be uistinct, as the author does not mention the small carina round the ■utural edge of the whorl, conspicuous in M. bicivcta when young, but much fainter when full-grown. The base too is less convex and the umbilicus more distinct. But these are minute differences, and from examination of a series, I am much disposed to unite the two species. Localitij. — Allumetto Island. There is another species associated with these, and differing chiefly by having strong upper and lower keels; and there ore several new Pleurotomaricef distinguished by their shortened form from the present genus. M. 8ERRATA, N. sp. Fig. 1. M. late conica, spird brcvi ; avfractihus 4 acuticarinatis, carlnis 4 scrratis, spallis intermcdiis concavis el striis conspicuis ; bad convexo, ore rotun- dato. The spire is less produced than in the preceding, forming an angle of fully 55* or 00°, and composed of four acutely carinatc whorls, deeply separated at the sutures. The body-whorl is furnished with four keels — the principal one vcnj jfrominent about the middle of the body-whorl ; one keel above it, near the suture ; another at an equal distance below ; on the convex base there is a fourth, which surrounds at some distance a rather large umbilicus, the sides of which are very convex. The keels are all more or less serrate, the principal one especially so (and not so much undulated as our figure shews) ; and the spaces between them are deeply concave — that between the uppsr keel and the suture nearly horizontal, but still hollowed out. The lines of growth are sharp and equidistant, decussating the keels to produce the serrate edges, and bending back considerably to the central prominent one, which is so narrow as not to shew a distinct band. This beautiful species is more sharply keeled than any other Silurian species known to me, and reminds one of some of the Carboniferous forms. Locality. — Allumette Islands. CANADIAN FOSSILS. II M. IIELICTERES, N. Sp. Piute IV. Fig. 2-4. M. turrlfa, hlvncialls, anfractif/us 5 sub-rofvndath, tricarinaiis anfiqvatis, ultimo viigo : carinis omnibus obtusis, mediand (cinguh) laid ; striis ciebris uspcris. This shewy species is not more remarkable for the irregular uncoil- ing of the last whorl (resembling in this respect certain varieties of the common snail, Helix asjicrsa*), than for the rough striation and antiquated appearance of the whorls. The band or principal keel is broad and flat, the upper and lower edges being prominent, and the middle only a little convex ; the rounded notch is rather deep. The upper and lower keels are obtuse, and equally distant from the band, the upper placed about half-way towards the suture, winch is not at all channeled ; its edge on the free whorl shews as an obtuse ridge. See figure 3 s. The spire is pyramidal, but the separate whorls are rounded ; the upper ones have the inferior carina covered by the suture, but it is exposed in the lower one by the divergence of the last whorlt figure 2, which afterwards becomes quite free, figures 3, 4. The striation is very rough and coarse ; the lines of growth cross- ing the ridges, give these an antiquated appearance. The mouth is round; the shell thickened, especially on its inner side. In the thick, obtuse whorls, coarse striation, and broad band, this species a good deal resembles M. scmirotimdata, McCoy, from the Carudoc formation of N. Ireland, but that species is destitute of the upper keel, besides having much rounder and more ventricose whorls. M. iricarinafa, Hall, (Pal. New York, vol. i., plate 3S, fig. 6,) is a Trenton species much more resembling our shell ; but his specimens are too imperfect to identify with, particularly as he mentions nothing of the tendency to uncoil, and distinctly says there is no umbilicus; the carinfe, too, are represented as sharper than those of our species. Moreover, the mouth is said to be ''acutely" produced below. It has, however, similar sharp prominent striae, and is pro- bably very nearly allied. Loccdiiij. — Common at Allumette Islands. ilf ■ See Gray's editioa of " Turton's Manual of British Shells." (Vignette.) CANADIAN FOSSILS. Section HORMOTOMA. Elongate, beaded forms, like ILlnpclla, but with a distinct band and notch, as in the other Murchisonia. Mouth rounded, not efluse. M. GRACILIS, Hall. Plate V. Figure 1. M. elongnta, biuncialis, anfractihus 10-13, vcntricosis, rolundatis (supra vix idanulatis), cingulo centiali lato, etiam quartam partem anfracl'ia. aquante. Synonym, — Hall, Palaeontology of New York, volume i., plate 39 figure 4; page 181. This gracefully-formed species belongs to a group of Murchisonmt which doubtless ought to be separated generically from the mort> typical angulated forms. They resemble Holopclhif McCoy (the 80-called Turritcllf. ITall, who compares it in this respect with tl." larger species, M IrUi'ui'ifK, of the same limestone. This slight angle does not how r ijitact from the general roundness of the volutions, as represented in the figures above referred to. It is an exceedingly plentiful species. Our figurfc'l specimen has the outer portion of the last whorl bro- ken away so r.^uch that the inner lip (a) looks far more conspicuous than it is in r>;ii ry. Tt is slightly reflected over the columella. Locality. — Abuvd; ut in the slabs of limestone at Pauquette's rapids, etc. OANADIAK FOSSILS. |> M. VENTBICOSA, Hall. Piute V. Figures 2, 3. M. turrlfa, avfractihus rotundatis centricosis Ircvigatu, mpeme subangula- tis, ct cirigulo lata marginato 2>rope suluram posito; oii , ninhiln. Synonym. — M. vcntricosa, Hull, Paleeontology o' New Yi-ik, vol. i., plute 10, figure 3. Th.v position of the band easily distinguishes this ' lo species from tl; ' *f. ' 'licincta, Hall, with which its size and gent ml shape would lead UB at first sight to identify it. It has the same proportioi of spire, and convexity of the whorls, and the pillar-lip is rai^riiL, as described by Hall, though his figures do not clearly >hew this character.* But the band, instead of being nearly central uw'' rather narrow, is broad, flat, and placed so high up as to be less 1 an its own breadth from the suture; while the lower margin fori s the prominent angle seen above the middle of the whorl. The lues of growth curve back much in the way figured in the M. ''>Uici icUi, and far less sharply than in M. gracilis, tending back to the b )ad band, in which they are much curved, and then forward again, h v- ing an open angle of about 100°. Any comparison with other allied species seems unnecessary, n -, except M. bcUicincta, there is no American species likely to be confounded with it. Pleurotomaria injlata, McCoy, Silurian fossils Ireland, is a kindred species, but quite distinct. It is found in tolerable plenty associated in the same slabs with the M. bicincla, Orthoceras arcuoliratum, Cyrtoccras Billiiigsii, and Sirophnmcna phinumbona, at Allumette Islands. Hall's specimens were found at the junction of the Birdseye and Trenton limestones in the Mohawk valley. Cyclonema, Trociionema, Eunema. Decade I. Plate VI. Cyclonema, Hall. Cyclonema, Hall. Mollusca Gasteropoda. Family Litorinidae. Turbinate, thin, of tiew ventricose whorls, with concentric striae • It is with some doubt thh ii rcfcrrod to Hall's very imperfect figured specimen. His description however agrcvH kci-urately, and it is useless to multiply names. 34 CANADIAN FOSSILS. or ridges, crossed by o'jlique, straight (or very slightly sinuous) linos of growth. No umbilicus. The mouth rounded, and with an imperfect peritreme. Inner lip thin, closely reflected, and a liitle concave. Trociionema, Salter. Trochonrmn. — Mollusca Gasteropoda. Family LitorinidtC. Turbi- nate, thin, of ■■ ,v angular whorls, marked by strong concentric .idges, and crossed by very oblique lines of growth. Umbilicus wide, open. Inner lip thin, scarcely reflected; peritreme com- plete. i ! EuNEMA, Salter. Euncmrr. — Mollusca Gasteropoda. Family Litorinidac. Turbinate thin, of few angular whorls, marked by strong concentric ridges, and crossed by strongly sinuate, prominent, and thread-hke lines of growth. Inner lip not leflected ; peritreme simple ; mouth rather efl'use below ; no umbilicus. 1 !\' LoxoNEMA, Phillips. Loxoncmn, — Mollusca Gasteropoda. Family Pyramidellidjc. Elon- gated, many-whorled ; aperture simple, attenuated above, effuse below; lines of growth (marking the form of the outer lip) sigmoidul ; no umbilicus. The characters of these four j^enera which have been liffured together are here given in order to shew in what points they dill'er, and what analogy and gradation of form subsists between them. Taking Trochomwa as the most dej)r(!ssed and widely umbilicate form, or with simple and very oblique lines of growth, the next step would appear to be Cijclonvma or lluhqvd, in which the umbili- cus is closed, and the lines of growth a little sigmoid, or at least sinuate, below. Eiiiirma. is still more elongate, and the lines of growth decidedly sigmoid ; while it is didieult to say if E. jnigoda more ])roperly belongs to this genus or to Loxoiinmn, in which the edge of the outer lip, indicated by the lines of growth, is sigmoid, and the entire form elongated. ! t CANADIAN FOSSILS. 35 Yet notwithstanding this apparent passage established by such forms as Et'ncma, it is probable that Lnxoncma belongs to an entirely different family (the Pi/ratnl dell idee), and that the rest are thin-shelled forms of LiforhiidcB, with an evident tendency towards the fragile lanf/diia, with which the rudimentary sinus in the outer lip also helps to connect them. Professor Forbes thought Tlolnpno, (and therefore Cijcloncma, which is closely allied,) much like Llilopo, a pelagic form of the Liforhdda, and they both have the concave inner lip of L'uorina. There is some difficulty in determining the nearest recent analogue of Trochoncma. It may be compared with Skaica (Lkorinida;) or with Adeorhis (i. e., Ci/clustremri), which differs from the other Tiochidae in its non-nacreous shell. Eimetna, it is true, has the sinus of the outer lip so much increased as to separate it from any recent forms of Lltoriiddd;, while it much resembles landdna or the allied genera Rccliizia, which has an an extremely simple, paludiniform shell. It has a much thicker shell, however, than these, and its affinities are with the fossil genera above described, from which the elongate form and sinuous outer lip effectually distinguish it. The fossil shells under consideration appear to be all too solid for comparison with floating shells, and the tendency they exhibit to form projecting and irregular apertures in old age indicates rather a ground-feeding and ultimately sedentary habit. Cyclonema. With regard to the limits between IMnpra and Cijcloncma, not much that is satisfactory can be said. The form is similar, and the strioL' or ribs are not always present in the one or absent in the other. The possession of a concave reflected inner lip, if it could be estab- lished for Cijclunema, would be a good character, yet certain species in the Canadian collection which are quite smooth, and luive the general character of //o/oj^m, resemble Cijv.hmcma in this, though they want the characteristic sculpture. IlilDpca seems to he sometimes (H. ohll({iia, Hall,) umbilicate, and sometimes not so. Cijdohcma is never umbilicate, and the inner lip is concave in the type species. L' accepted as a genus, Cijdoncma should include all those Silurian species hilh(>rto referred to Turbo, Euomidialiit, etc., which have concentric ridges and oblique lines of growth. Although this is only a superlicial character, it is found in so many species, that, combined with the thin shell, it may be taken into account. 26 CANADIAN FOSSILS. Euompfialus granulatus and E. Uneatus, Portlock, Turbo crehristria, McCoy*, and T. sulcifcr of Eichwald, in addition to those described by Hall, will certainly fall into it. These, with numerous concentric ribs, none of which are specially prominent, lead the way easily to such forms as T. rujicstris, Eichwald, in which most of the ridges are suppressed, and a few large ones only remain. The bands of color follow the direction of the ridges in the last named elegant species. T. trimarginatus, Eichwald, is another similar form. It is difficult, if not impossible, to draw the line between such species as these and the several gradations which lead back to C. bilix or the fossil here figured. The group appears to range into the Devonian rocks, aa we learn from the figures of the MM. Sandberger of Nassau. il i .1 C. Halliana, N. sp. Plate VI. Figure I. C. turhinata, ventricosa, aiifractibus 5 rotundatis, supra paullulum plana- tis, — ultimo ad basin gibboso, striis que concentricis undulatis cincto ; basl suba?)gida(d laivi; ore rotunda. It is not difficult to distinguish this from the C bllix ( Plcurotomaria bilix, Conrad), for the whorls are much rounder and the spire conse- quently fiot nearly so conical ; the stria? only cover a part of the whorl, and the pillar-lip is not so straight or so much reflected. The species are however very closely allied. The whorls are rounded, and even rather gibbous toward the lower part, but there is a decided flattening above, and the base too is a little flattened (not nearly so much as in C. bilix). The lines of growth are oblique backwards, as far as the basal angle, if it may be so termed, and thence turn forward, making a slight sinus. [This character is even more decided in the C. bilix, and is greatly exaggerated in the genus Eunema.'] The suture is well pronounced, the upper part of the whorl free from concentric striie, which occur only on the sides ; the base also is smooth. The mouth is roundish, a little prominent only beneath the columellar lip, which is not quite vertical, nor is the inner lip much reflected or more tlum slightly concave. Localitij. — Pauquette's Rapids. * Palaeozoic Fossils, Woodwardian Museum, Cambridge, Plate 1 L, figure 22. CANADIAN F0S3ILS. It C. SEMICARINATA, N. Sp. Figure 2. C. semiuncialis, spird rcgulari/er conicA,, nisi suturis horizonfalibus inscctd ; slriis obscuris ; anfmctibus 4-5 supra biangulatis, ivfra Qt-carinatis, carind secundd maximd mediand, quartd pirominuld ; ore rotundo. Of this well-marked form there are only two or three specimens, the largest not above half an inch in height. They were first taken for Pkurotomaria pcrcaririafa, Hall, which, as it shews nothing of the characteristic band or notch, may very probably belong to Cijcloncma. But in that species the sutural space is not horizontal, and the conical spire seems therefore blunt instead of deeply incised, while the keols below the chief ridge are mostly equal. There are two or three other species in the Ottawa limestone, one beautifully ornamented, and like a Plcurotomaria in everything except the notch. Locality. — Allumette Islands. Holopea obliqua, Hall, accompanies it. Trochonema. Under this proposed name will fall several Upper and Lower Silurian species, such as the Turbo trochleatus of McCoy, and Euom- phalus tricinclus of the same author; only those however with the strong concentric ridges possess a wide umbilicus. Luichus angulatus, Hisinger, is probably an extreme form of the group, with a greatly depressed spire. Fleurotomaria umbllicala, Hall, is the one here described, and the type of tlie genus. T. umbilicata. Hall. Plate VI. Figure 3. Troch. nnciam lata, depresm; anfractibus pcrangulatis, facie extcrnd laid verticali ; umbilico latissimo, tumido, carind obtusd ycrmarginato. Prof. Hall, Pahcnotology of New York, vol. i., plate 10, fig. 9, and pi. 38, fig. 1 ; p. 43-175. Turbinate, depressed, the last whorl often free; the spire short, truly conical, interrupted only by the vertical faces of the whorls and the hollow sutural edge. Volutions, 4 or 6, with 4 carinae, of which two ] ni 28 CANADIAN FOSSILS. H . ' on the middle of the whorl are strong, prominent angles, enclosing a broad, vertical, slightly concave space (the upper angle rather the more prom"nent); one close to the deeply canalicuhitcd suture; the fourth only visible on the base, margining a very broad unibilii^us. The space between the upper and second carina is more concave than that below the latter, while between the third and fourth the space is a little convex, not quite flat. The umbilicus is first concave and then tumid ; it exposes the second and part of the third whorl. The mouth is round-ovate — the obliquity from above outwards — and thickened at the basal angle formed by the lowest keel. Hall's specimens are all more or less distorted and compressed ; hence his descri[)tion, though accurate, does not fully agree in all points. The character of the angular volutions, with the concave spaces between short depressed spire and wide umbilicus, enables us to recognize the species; and I am further assured by Mr. E. Billings that there is no doubt of their identity. But the species must be more variable than the Canadian specimens shew, since Hall figures and describes forms (i)late 3S, figiu'e Ig) more elevated, and others (plate 3S, figure Ic, and plate 10, figure 9hJ more depressed than any of ours. The base of none of his specimens isventricose, and I think that must be due to oblique pressure in his specimens or to their being mostly internal casts. The description, by Prof. McCoy, of his Turbo trochlcafus* agrees well with ours, except in the rounded base and small umbilicus ; it has a less deep suture, as his figure shews, and the space between the two bands on the whorl is decidedly narrower. These ditlerences are here noted particularly, as I had provisionally referred the Canadian shell (see Reports British Association, preface) to the T. trochlcafus, McCoy. Now that we know the position of the Galwiiy rocks as Middle Silurian, it is the less likely that any species should be in common with those of the lowest formations of Canada. PLurotomatia lufi/asdata, of the same author, is another spCv^ies so like ours, that it seems hardly distinguishable, except by the longer sp ire. Locfdifij. — T. umhiliatta is a common species occurring in nearly all the slabs from Pauquette's l\ai)i(ls. It ranges from the Birdseye to the Trenton limestones, in New York. 4 * Silurian Fossils, Ireland, plaic i., figure 9. CANADIAN FOSSILS. t» EUNEMA. The typical species may be considered E. sfrig'dlata, which has an elongate form, and the strijR bent forwards below the sinus; while there are others with the lines of growth vertical below, or scarcely at all brought forward. These latter connect it with the Cijchmcma, but have still the produced mouth and more turrited form, which gives them the aspect of Murchisonia. E. STUIGILTiATA, N. Sp. Plate VI. Figure 4. E. turlinafa, cloyigatOy anfmctlbus 6 obliqiiis, socpc vngis : cnrinis trihus (equidisfantlljus, svpciiori ad siifurum, sccunda siqira medium positis ; cunctis a st/iis aspcris dkkotomisijuc dccussatis; ore ovato. This beautiful shell is quite abundant at Pauquette's Rapids, and many finely-werithered specimens nhew t.ie characters well. It is a thin shell, and the striations of the surface are remarkably sharp, prominent, and regular. Shell elongate, turbinate, of about six rather oblique whorls, the last sometimes free. There are three prominent ridges on each whorl, the principal one placed much above the middle of the body- whorl, the upper one near the suture, the lower at an equal distance below the median keel. All are crossed by equal, fiharp, close, thread-lik(! ridges of growth, which tend about 00° backward to the principal keel, where they are sharply bent, and proceed a little forwards over the sides and ba^e ; the open angle of the notch so formed is about 1:30''. Tin^y bifurcate regularly between the upper and middle keel, and re-unite in pairs upon the base, which is produced. The mouth is oval, a little pointed above, and below Bomewijat effuse. There is no umbilicus, and the inner lip is not reflected or pressed closely against the columellar base, which has a slight angle upon it. Localiiij. — Pauquette's Rapids. m to CANADIAN FOSSILS. E? PAGODA, N. sp. Plate VII. Figure 5. E. turrita, ehvgatissima, anfructihiis 10-11 dcprcssis trlcarinatis ; carind supcriori remotd minimd, suturam pmfundam approximatd ; mcdiand inferiorique fere cBqualibus, cminentibus : cunctis crcnulatis, striis obscuris (rctrorsis ?). A much elongated, turrited shell, of about ten or eleven very convex beaded whorls, very gradually increasing in size, and furnished each with two prominent keels, besides a smaller one along the sutural edge. Of the principal kef^ls the upper is rather the more prominent, and placed about the middle of the whorls in the spire, but above it on the body-whorl. The space above it is a regular slope, between it and the third keel concave, and below the third also concave for a somewhat greater space as fur as a fourth, which only shews on the base of the body-whorl, being covered by the suture in the spire Mouth, unknown. The keels are all more or less crenulatcd, evidently by the lines of growth, but these are so obscure that it is impossible to say whether they are oblique backwards, as in Eimcma, or arched forward, as in true Lnxoncma. The species might be referred to either of the two genera, but as yet we know of uo Loxoiiema with strong spiral keels, while they are characteristic of Eiinami; it is therefore safest to leave it in the present genus, especially as there are other smaller species not described here, of quite as elongate a form, in which the course of the lines of growth is not doubtful. Locality. — Frequent on slabs of limestone, in company with many of the foregoing species, at Pauquette's Rapids. Another new spe- cies resembles a small Cerlthiicmt and might be termed E. ccntldoidcs. LoxoNEMA, Phillips. The species of this genus are but rare in Lower Silurian rocks. One is introduced hare to compare with the most extreme forms of Euncma. The inner lip is still more incomplete, and the curve of the 8tria3 more signioidal. m CANADIAN FOSSILS. M L. MURRAYANA, N. Sp. Plate VI. Figure G. L. 2J uncias longa, avfract'ihvs rcgiilaritcr covvcxis etiam ivflatis, ne supra julanulalis, (ad sufuram vallo angusto notatls,) striis conccntricis obscuiis, striis incremcnti conspicuis, antrorsnm arcuatis : umbilico nuUo; ore ohovato. The length of this species must have been full two and a half inches, and the diameter of the lower whorl not less than three quarters of an inch. The whorls are very convex, almost inflated, and have no special prominence in any part ; their base is a little produced. The sutural edge is a fine raised thread, and beneath it occurs a narrow flattened space (with a raised border on the lowest whorl). There are a few faint concentric strife, but the lines of growth are the only prominent ones ; they are strong, sigmoid, the backward curve short, the lower forward one a broad arch, reaching further forward than their origin at the suture. There is only a minute umbilical depression, with no bounding ridge, and the inner lip is incomplete, its edge simple, not reflected. A single specimen only has occurred of this fine shell, and I have pleasure in naming it after Mr. Alexander Murray, who has labored so long in the Canadian Survey. Localifij. — Pauquette's Rapids. Murchisonia (Loxonema?) suhfusi- ortnis, llall, appears also to occur in this limestone. Cyrtoceras, Goldfuss. Generic characters. — Cyrtoceras, Goldfuss. Shell curved or partially involute, sometimes with the transverse, at others the longitu- dinal, diameter the greater. Aperture often contracted (in the smooth forms). Siphuncle subinternal, central, or external. (Barrande.) Section Cijrloccras. — Curved ; siphuncle variable in position, simple, Gi/roceras. — Involute; siphon internal or subcentral, solid, radiated. It is not easy, in the absence of a perfect structure in the siphuncle, to separate Cijrtoccras from Gtjroccras, the principal difference being the more regularly involute form and ornamented surface in the latter (just as in the case of Toxoceras and Crioceras among the genera with foliated septa). ? I I I \ 1 1- M CANADIAN FOSSILS. Indeed it is much to be wished that a name so ill applied as Gijroccros slioiihl be abolished aUogether. Originally given by Meyer to the Sp'indn cnmprcssa of Von Ruch, which has since proved to be a Goniaiiics, i\l. d'Orbigny had no warrant for applying the name to a totally different form. And as the jmslfhn of ihe siphon will not distinguish the two genera, there remains but the somewhat obscure character of its more solid rwiuiled structure to separate the two genera. It would be better to reunite them, and when the value of this chnracter is better known, to complete the chissification. We are fortunately able to present two extreme forms of the genus in one plate: the one smooth on the surface and much laterally compressed, as in the several Silurian forms; the other ornamented with large, frill-like varices of growth, and with a wide section, like those of the Devoniau species. Some of these latter (referred to Cijrtoccras by Goldt'uss and Phillips,) are as much involute as a Lituiics, and are wide in section, the fore and aft diameter, so to speak, being less than the tranverse measure. Cyrtoceuas falx. Decade I. Plato VII. Figure 1-4. Synonym. — C.Jalx, Billings. Report of Progress, Geological Survey of Canada, lSo7, p. 314. A smooth shell, or with very faint and nearly direct lines of growth. It is strongly curved, and somewhat compressed, about two inches long, ra^tidly tapering from ten lines broad to two and a half, and iu some specimens more quickly. Aperture oval, ten lines broad by eight thick. Siphon nearly close to the peripheral margin. Se[)ta close, concave from back to front. I have Ml'. Billings' own authority for identifying this shell with the species described by him, else I should have regj'rded it as rather belonging to the other allied species (from the same locality) which he has termed C. simpler. As the specimen figured — and others still more perfect — are in the Canavlian Museum — I beg to refer to his descri[)ti()n in the Report of Progress of the Geological Survey, published 1S07, pp. 3L'-i, 314,) for the specific characters. It might be compared witli C. macrostomnm, C.arcuatum, and C.iumurum, Hall, but all have more distant septa. Locality. — Pauquette's Rapids. CANADIAN FOSSILS. 33 C. BlLLINGSII. Plate VII. Figures 5, 6. C. 2-3 unciale, in juvcntule subcijlindricuin involutum, in cetate depresso- ovale, rcctius ; anmdis rcmotioribus elevatis undulatis in dorso sinuatis ; scptis apirroximatis plants, siphunculo extcrno ; suum diametrum a marglnc remoto. Sijnonym. — C. lamellosum, Hall, Palfeontology of New York, vol. i., plate 41, figure 2 (not of DeVerneuil and D'Archiac). Prof. Hall's description, taken from a young and very imperfect specimen, is clearly applicable ; but this species must receive a new name, since the C. lamcllosum, a nearly allir d species from the Eifel limestone, differs both in the less rate of increase in the whorl, and the lamellfe are much closar. The curve of the tube is also more gentle. But for these proportional characters, which however are quite sufficient in this genus, it would be difficult to separate the Devonian species, which the Professor aeems to have overlooked, as he describes his fossil as new. I adopt such parts of his description as are applicable to the adult form. Subcylindrical when young, at a diameter of seven lines (and regularly involute V), but soon attaining a more open curve and becoming laterally expanded, the dorso-veutral diameter being to the lateral as nine lines to thirteen, when this diameter is attained. The tapering is more rapid in the young than in the adult portions. The lamelhe are rather coarse and somewhat irregular in distance. (C. himcUosum has them very close and regular.) In figure 6 they are not more than a third of a line apart in the young portion (a), and less than a line distant in the older portion (b), while iti figure 5 they are fully two lines apart in the same diameter, and become closer again in the adiilt portion (b), where the distance is again not more than a line or a line and a half.* Their course is direct over the sides and inner margin, but on the outer (ventral) surface they turn rapidly backward, forming a distinct sinus. They are rudely fimbriated, with " transverse, undulating, squamose lamellae, abruptly bent backwards on the dorsal line," and several obscure, longitudinal furrows cross them. " The spaces between the lamellae are marked • Cuch a change in the ornament is not unfrequent in the Cephalopoda, and indicates probably a more vigorous growth in middle age. 1 1 i \\ 84 CANADIAN FOSSILS, by fine transverse stria)." Septa close (Hall), very flat. Siphuncle small, its own diameter distant from the outer or ventral* border. Of this elegant species only two examples have as yet occurred, both of which are figured. LncaUtij. — Allumette Islands. C. anmdatum, Hall, is more rare. Orthoccras arcuoliratmi, O. hilincatum, and O. laqucatum, are also found, the first very common indeed ; and the Gouloccras anceps of the Black-river limestone occurs with these. (See Preface.) 4 Ctenodonta, Salter. Ctejwdonta, Salter, 185]. Mollusca Lamellibranchiata. Familj^ Arcacidie. Nearly equilateral, generally transverse, anterior side largest ; beaks, approximate, not prominent ; hinge-lint with a double series of bent teeth, connected by smaller orea beneath the beak; ligament posterior, external, on a fulcrum : no striated area or cartilage pit ; muscular impressions strong (with supplementary scars), not bounded by elevated ridges; pallial line simple. I was not aware, when I proposed the above generic term for a group of paliEozoic Nucula't, that the principal species had hi: a previously published under tlie name of TcUinomija by Prof. Hall. His recent descriptions^: shew this to have been the case, and if the name did not convey an entirely erroneous view of the affinities, I should have been glad to restore it. But the chief characters of the genus reside in the hinge and teeth, which are neither figured nor described by him, casts only of the interior and the external surface having been given in the plates of his excellent work, nor was the external ligament observed. Mr. S. P.Woodward, in his most able treatise on the Mollusca, has included my proposed genus under Isonrca of Munster, a group of nuculoid shells which have the peculiarity of Clcnodonla so far as the external ligament is concerned. But in Isoarcn there is a ligamental area, as in Area and CuciiUaa, and the tumid beaks are remote, • The outer margin is often called dorsal, but there is an objection to using terms in direct contradiction to the anatomical structure. t Reports British Association, 1851. Trans. Sect., p. "3. t Descriptions of New Pnlfcozoic Fossils ; extracted from the Reports of the Regents of the University, Albany, 185G, p. 142. CANADIAN FOSSILS. 85 subspiral, and in the typical species (I. cordiformis, Scluiblcr, nnJ /. siilsinrnta, Minister,) qnite toward one side. It may be doubtful if such species as /. liiuata of Munster and Niicuhi elliptica of Gohlfuss, whicli have subcentral boakJi, do not belong to Ctciiodonla ; they are smooth, or with a concentric lineation only, while Isourca is often cancellate. Soknclla, Sowerby, has an external ligament like Ctmodonia, but a notched pallial line. The genus has been referred to in the tliird edition of " Siluria," p. 213, 859. It will include, as I believe, all the Silurian Nucula3, and a considerable number of the otlier Paheozoic species. It pro- bablv extends, as above stated, into the Trias. C. NASUTA. Plate VIII. Figures 1, 2. C. hlunc'idis cl ultni, fransverso-ovuta, Iwris, nisi (intici riigis cnnccDtricis; latere aiiticn rotundato, iiostico suhcuntraclo clovgato, hand carinato ; umhoiiihus dcprcssis. Stjnomjm. — Tcl/ino7ni/a 7iasuta, Hall, Pahvontology New York, vol. i., plate 34, figure 3. Ctcnndonta Lngani, Salter, in British Asso- ciation Reports, 1S51. Trans. Sect., page G3. I.soarca Lognni, Woodward, Manual Shells, page 2(59. TcUinonvjd nasuta, Hall, Report of the Regents of the University, Albany, 1S57, p. 143, fig. 1-3. A beautiful species, not unlike in shape to some species of Anatina or Thracia, and, from the subcentral position of the beaks, very unlike the usual appearance of N//ci//a. It is the largest known species of the genus, full two and a half inches wide, by one inch and a quarter long, measuring from the slightly prominent beaks, which are much nearer the anterior than the siphonal end. The depth of the valves, united, comprises three fourths of an inch. The general contour is transversely ovate. The anterior side perfectly rounded and marked with concentiic rugfv, which are strongest on the upper portion. The posterior side narrows consi- derably, and is a little contracted at the posterior third; its surface is smooth and gradually less convex towards the subtruncated end ; 30 CANADIAN FOSSILS. the posterior slope or ridge only excepted, whicli is convex, but not at all cariimte. There is a slight groove below the straight cardinal border. The ligament fulcrum extends to full half an inch from the beak, and the ligament itself (often perfectly preserved in the silex) is conv(!X, and rather conspicuous. The teeth are straight, vertical, and set on a moderately broad edge; there arc about eleven or twelve on each side, arranged nearly in a direct line; the hinge-plate which bears them is narrowest on the anterior side, and beneath the beak much contracted in depth. (In the next species it is considerably broader. Locali/ij. — Allumette Islands. A new species of Lijmdcsma occurs with it, distinct from L. i>lana of the Trenton limestone. C. LOGANI. Plate VIII. Figure 3. I ; C. nnclalh, convcxa., ntitica mtunduta fcrc gihhd, posdce svlttrKiicota ohtiisi- airhidtn; umhonc suhcentmli cmlncntc; dcntibus anticis 7, posticls 9 curvutis. Si/noinjin. — TcIliiiDmija ihih'in, JlaW, Report Regents University, pi. c, figures 4, 5 (not of Pal. New York, plate 34, vol. i.). An elegant species, which might, till closely examined, pass for a variety of the last. It is mucli more convex, and almost gibbous anteriorly : the posterior side more decidedly contracted and sub- carinate above. The beak is rounded, but elevated and placed centnill3% or rather nearer to the subtruncate posterior end than the other. TlKsre is no lunette. TJie teeth are placed on a gently curved hinge-plate, which is not indented by so prominent a ligament fulcrum as in the other speeios. Those on the anterior side are straight, prominent, and simple; the posterior ones are bent towards the centre, and those beneath the beak crowded, no space being left between the anterior and posterior sets. The anterior shews that the adductor impressions were not so deep as in the next described and smaller species. As the larger fossil above described camiot bear the name I had originally proposed, and as the name Ctenodonta Lngani has appeared CANADIAN FOSSILS. 37 in print, I wish to apply it to this fine spccios. Professor Hull has fio-iirod it uiiilor tho nume diiljla, but th« figures given in liis Pula'ouiolouy of New York, plate 3 1, shew that species to have been smaller and w Mer, the "length almost twice the height." It is much more gibbous too, according to his figures, the edge beinj: turned quite abruptly inward, ^Iv. iiillings, who has seen specimens of tlie C. duhid, assures mo ihey are distinct. Localitij. — With the last. Hare. C. CONTRACTA. is not spof'es. Iso deep |e I had >peared m Plate VIII. Figures 4, 5. C.jxirnthi, trcsparlcs unc'uE lata, trlgonula, Riilhrqu'ihttcra, aiiticv rotuntluta, liostice ciincata carhiata contractu, innhiiiiihus clavat'is jyra: medium liositis ; lunidd distiiictd; cardine dcnlihuH majonbus. Synonym. — TclUnomya cuncata, Hall, Report, 1. c, figures 0, 7. A common but pretty little species, which well illustrates the character of the genus as distinct from Xuciila or Lcda, to either of which it bears a strong resemblance. Instead of two rows of teetli separated by a spoon-shaped process to carry the ligament, the two rows run into each other, with only a slight angular notch to separate them, and the ligament is clearly seen outside, set on its prominent fulcrum. The form is that of a wide triangle, with the gently elevated beak rather nearer the anterior end. This is rounded into the ventral border, which has its greatest convexity in advance of the line of the beak. The shell too is most convex here, and a depressed line separates the elevated and carinate siphonal ridge. The posterior cardinal slope is Hat in some specimens, and nearly so in all ; the ligament fulcra marked out on it as a long oval lunette extending half-way along it. A similar lunette, more deeply sunken, marks the anterior side. The ligament itself is but small. Teeth about six or seven on each side ; beneath the beak a few crowded ones occur; they are straight, or nearly so, and set obli(iuely inwards on both sides of the broad, bent hinge-])late. The beak considerably overhangs the hinge (fig. 5a). Tlie shell is thick, the impressions of the adductor muscles deep, and close under the hinge-line. A small accessory scar occurs above V!' if li 38 CANADIAN FOSSILS. each impression. A thickened ridge lies on the inner side of each, strongest behind the straight-edged anterior impression. Fig. 4 shews the variety with the flat or vertical posterior slope ; fig. 5 has it slightly convex. Locality. — Plentiful in the Allumette limestones. C. GIBBERULA, N. Sp. 6 I tt ^ Plate VIII. Figure 6. C. suhtrigona, rudis, 9 lineas lata, margine antico cardinali gihho ; latere antico magno^ convcxo, lunuld nulla ; iiostico hnvi suhcarinato ; cardine dcnt'ibus modicis. Differs from the last by characters not very obvious at first sight, but these grow more evident by study, and it seems to bear the same relation to C. contracta that the C. ohtusa does to C. Lomni. The form is trapezoidal rather than triangular, and of unequal sides; the posterior bluntly pointed and small ; the anterior large, gibbous and rounded ; the ventral margin almost straight. The beak is conside- rably nearer the posterior side. It is not very prominent, the valves being most convex all along the anterior slope which overhangs the hinge-margin all along ; the sinus which separates the somewhat pointed posterior side falls under the beak, and consequently near to that margin ; and the posterior slope is bluntly carinate, and so short as to be not far from vertical. The ligament fulcra are marked out by a narrow lunette, which the beak overhangs. The hinge-plate is bent at an obtuse angle, and bears about ten teeth on each side, which are set obliquely, as in the last species. The shell is thick, but the muscular impressions are scarcely visible in our specimens. A few antiquated lines of growth near the margin shew that our specimen is full-grown. Notwithstanding the above important differences, there is much similarity to the last species in habit, the distinction being chiefly due to the exaggerated development of the anterior side. Localitij. — Not uncommon in the Allumette limestone. CANADIAN FOSSILS. 89 C. ASTARTJEF0RMI8, N. Sp. Plate VIII. Figure 7. C. crassa, vix semipoHicaris, trigona, nate curvo, excdso: margine postico leiite concavo, reliquis convcxis ; superficie lineis crebrissimis ritgisque conctntricis ornatd : dentibus pluribus, /metis. A small, thick shell, higher than wide, triangular, with a greatly elevated and somewhat curved beak, and the surface covered with fine equal concentric striae, besides four or five rugae or varices of growth. The posterior side (at least we must suppose this to be the posterior side from analogy with other species of Nucula, — the beak is however extravagantly raised ;) is gently concave without a dis- tinct lunette, the posterior and ventral margins arched ; the whole figure is triangular. The interior shews a flat hinge-plate, broadest beneath the beak^ but with no cavity for a ligament, which must therefore have been external, though no fulcra are visible. The teeth are numerous and V-shaped, extending far down the posterior hinge-plate, and half-way down the anterior side. They are either absent or very small imme- diately under the beak. This beautiful species exactly resembles at first sight one common in the Lower Silurian rocks of Wales, the C. (Nuc.) varicosa, Salter, and it is difficult to say how they differ. But while the Canadian fossil is a solid shell, the British species is a very thin one, and it is the interior cast of the one that resembles the outside of the other. Locality. — AUumette Islands. Ortiiis tricenaria, Conrad. Decade I. Plate 9. Genus OrtJds, Dalman. Mollusca Brachiopoda. Family Orthidae. Shell punctate, squarish, rounded, or transversely oblong (the hinge-line generally narrower than the shell), radiately striated or plaited, convex in one or both valves; hinge-line with a fissure open in both valves* ; dorsal valve with divergent short teeth, and a simple cardinal process between them ; muscular impressions roundish, and circumscribed in the dorsal valve. • In Orthisina and Streptorhynchut the fissures are closed, subgenera of Ortbis by some authors. These are regarded as i I 40 CANADIAN FOSSILS. 'i 3 11 iii' Specific character. — O. rotundata iwllicaris, valvd dorsali pland, vcntrali gihhd cardine, in latitudinc testam cBquantc ; arcd magnd suhairvd ; foraminc angustissimo. Costa radiantcs convcxa, circitcr 30, interstitiis angustissimis in valvd dorsali scepe filiferis ; striis transversis incon- spicuis. Synonym. — O. tricenaria, Conrad, 1843. Proc. Acad. Nat. Hist. Soc, vol. i., p. 333. Hall's Pal. New York, vol. i., p. 121, plate 32, figure 8. There could scarcely be better examples of specific character, as distinguished from mere variability, than are exhibited by four shells? two American and two British, among the large plaited Orthides of the Lower Silurian rocks. Of those, Orihis tricenaria, the subject of our plate, is precisely analogous to the English fonii, 0. actonice, Sowerby, while 0. pectinella, of Conrad, another American species, with nume- rous varieties, equally well represents the O.jlahellulwn of Snowdon. Yet while all these species so much resemble one another that they might easily be confounded, each is distinguished by characters as neat as they are constant. O. Actonice, Siluria, 3d edition, p. 209, fig. 82, has few strong angular plaits, frequently bi- or tri-furcate at their ends, and the ventral or receiving valve is the convex one, the dorsal being concave. In O.jlabclJuhim the reverse takes place, or the larger ventral valve, although prominent at the beak, being much flattened and actually concave, while the convex valve is the dorsal one. This difference is constant, while the fewness of the ribs in both distinguish them from the variable O. call/gramma of Dalman, which has both valves g«'ntly and equally convex. The same relative differences are observable in the two American species above quoted. O. tricenaria has the ventral valve the large one, and the other flat or even concave, while O. pectinella possesses a well-defined convex dorsal valve and a concave ventral valve, the beak of which is nevertheless prominent, as it is in O.jlabdlulum. Both again are distinct from the O. plicatclla, which represents in America the O. calllgramma of Europe, and, like it, has both valves convex. O. tricenaria is of a semi-oval or even subtrigonal form when young, and in age is subquadrate, from the greater extension of the front than the sides, with length and breadth very nearly equal. Dorsal valve (fig 1), flat, concave at the beak, its hinge-line straight, produced into very short ears; ventral valve (fig. 2), strongly convex, even gibbous, its beak much elevated, but not at all incurved ; CANADIAN FOSSILS. 41 area oblique, broad-triangular (about 140°) ; foramen almost linear, continued quite to the apex. Surface of both valves closely radiated by about thirty convex, rod-like ribs, with narrower interstices, the ribs quite simple in the ventral valve, but interlined in the upper or dorsal valve by fine regular threads. All are crossed by delicate, inconspicuous striae of growth. Old specimens are antiquated near the margin. The shell is thin ; the interior is deeply scored, for some distance from the margin, by conspicuous furrows between the ribs ; each rib is impressed by a median groove. The space for the muscular impressions in the ventra,! valve (fig. 3a), is moderately large, rhomboidal, bilobed at the base, cir- cumscribed by external blunt ridges, and divided by a very slight median one. The hinge-plates are very short, and diverge at about 80O. The ovarian spaces (b) are well marked. The interior of the dorsal valve (fig. 4), with the muscular impres- sions very strongly marked (b, c), shews them divided by a broad, rounded ridge. The brachial processes or hinge-teeth (a) are very short, diverging at 50°, and with a linear central tooth (cardinal process), which bisects the narrow foramen, and bends backward with the area. The ribs shew very strongly in the interior, fully half-vvuy up the shell. The area in the dorsal valve is flat, and forms an angle of 50*^ with the valve itself: that of the ventral valve is inclined at about 70^ ; it is very little curved. The two areas meet at about 120^ in the young shell, and about 90° to 100^ in the adult. A great advance was made in the classification of the Brachiopoda by DaliTian, when he established the genera Orthis and Leptacna for the numerous Silurian species he was acquainted with. And little has since been done for the family of the Orthid(B, except the sub- division of the former genus, and the separation from both of the flat, semicircular forms now known under the name of Strophomcna. The three genera arc clearly separable, if account be taken of the general habit, as well as of the characters of the hinge and muscular impressions, for while Lcptccna has the valves involute, and the muscular impressions of the entering valve greatly elongated, Strophomcna and Orthis have these four impressions subquadrate and arranged in a circumscribed group, Strophomcna being further distin- guished from Orthis no less by its expanded flat form, than by the large bilobed cardinal process between the teeth in the dorsal valve. In Orthis the process is simple, often linear, and the two teeth I!i) '5 li 'ill' f -i ' li 43 CANADIAN FOSSILS. divergent at a much less angle. The hinge-line of Orthis is variable in width, often considerably less than that of the shell. In Stro- phomcna it is rlways as wide as the widest part of it. Orthis has generally one, sometimes both valves convex. Sirophomena has both valves flattened, and generally one bent over the other. And while the impressions of the blood-vessels in the mantle of Orthis are radiating and but little curved upwards on the sides, those of Strophomena take a wide upward bend, and quite encircle the ovarian spaces. The range of the three genera, thus defined, is somewhat different. Orthis is the earliest, beginning in the period of the Lingula flags, and reaching upwards by one or other of its subgenera to the Permian rocks. Leptana began not quite so early, in the Llandeilo flags, but maintained its position till the Oolitic period ; while Strophomena, more restricted than either, commenced apparently at the same period with Lcptccna, but is not known later than the .Devonian epoch. Some authors of repute (M'Coy, Woodward, etc.,) regard StropJwmcna and Leptana as mere subgenera, but I prefer, as Mr. Thomas Davidson has done, to give them each generic rank. The separation of the four subgenera, — Orthis (Dalman), Orthisina (D'Orbigny), Stveptorhynchus and Platystrophia of King, is quite convenient, and of geological value. The range of the true Orthis is the most extensive, and the possession of an open triangular foramen in one or both valves, distinguishes it from Orthisina, a Lower Silurian form. In this both valves have a closed deltidium, a small circular hole only being left in the apex of the larger valve. Platystrophia, which has the form of a Spirifer, and an open foramen in both valves, is Silurian only, while Strcptorhyiichvs, (which, in the form of the teeth and hinge-plates) is most like Orthisina, has a wide area, and is attached by the twisted beak. It is an irregular form, characteristic of the Carboniferous and Permian strata. Locality. — Pauquette's Rapids, in tolerable plenty, with Stropho- mena plannmhona and S. filitcxta {S. alternata. seems to be absent). Wiynchonella incrcbcsccns and Peutamcrus {atrypa) hcmiplicatus of Hall are here. Taey are both Trenton fossils, and there are one or two other species of Ilhynchonclla and of Orthis, of smaller size. i. I CANADIAN FOSSILS. 43 RECErTACULITES. Decade I. Plate 10. Generic character. — Rcceptaculites, Defrance. Sub-kingdom Protozoa. Order Foraminifera. Family Orbitolitidae. An infundibuli- form disk, composed of vertical cells in a single series, having rliomboidal thickened apices at each extremity : the casts of these cells within are thick cylindrical columns (of sarcode) connected by transverse stolons at their upper and lower ends ; and by smaller ones in the middle of the columns. The clearing up of the affinities of a single doubtful fossil is never barren of good results, since it may tend to throw light on other forms as little understood, as well as upon the conditions under which the organisms lived and were imbedded. And if, as in the present instance, it should be rendered probable that an extinct form was of much greater size and importance than its living conge- ners, the excessive development in earlier times of a type now existing, is a fact quite as significant in its bearing on the history of organic life on the globe as the absolute replacement of one group by another in geological time. The genus Rcccptac^ditcs has long been known, having been described and figured by Defrance so early as 1827, and quoted by De Blainville from the Devonian rocks of Belgium. It is known in the Silurian strata of Australia and in the northern parts of the American continent, but has not yet been detected in strata of that age in Britain. It has been referred to plants, and doubtfully to corals, but still remains where it was first placed, among i,he group of " Incerttij Sedis." It does not seem to have occurred to naturalists* that a form fre- quently five inches in diameter and not less than an inch in thickness could be referable to the group of Foraminifera, and be allied not very distantly to the genus OrbholUcs. But the excellent figures and elaborate descriptions by Dr. Carpenter of thir^ group of the Forami- nifera, and especially of some large species from Australia and the !'• • Except my friend Mr. T. R. Jones, who, some years back, perceived the analogy in form, but neither he nor myself at that time took any further notice of it. I had forgotten his observation when Dr. Carpenter's memoir appeared. It is due to him to recall it. ■f I '-! ' I ! I'll] ■n; 44 CANADIAN FOSSILS. South Sea Islands, shew a great resemblance to our fossils, which on closer study becomes more striking ; and I am induced, notwith- standing slight differences of structure, to regard Rccepfaculites as belonging to the same family, and as having a greater resemblance to the complex than to the more simple forms of the Orbitolitidge. It will be desirable first to shew what is the structure of Orbito- lites, as given by Dr. Carpenter in his memoir, "Trans. Phil. Soc," volume for 185G. If the enlarged figure with vertical and horizontal sections in his plate 5, fig. 0, be taken, as he intends them, to shew the general structure of a compound Orbitolite, it will be seen that the greater part of a vertical section through a disk is occupied by the simple columnar cells which form the basis of the whole struc- ture, and which are produced in successive rings around the globular central chamber. The cells of one ring alternate with those of the next, and form, when the superficial layer is removed, or as seen in horizontal section, a quincunx arrangement of circular cavities. Each ring of cells is connected with the next by small perforations giving passage to the minute stolons of sarcode, and of these there Is only one to each cell in the simple forms, but they are numerous in the more complex varieties. Besides these small connecting stolons which link together the cells of one circle with those of the next, there are others, concentric ones of large size, which connect the cells laterally, there being in the complex form an upper and a lower great concentric stolon running along the top and the bottom of all the columns. It is from these stolons that the superficial segments take their rise, and not directly from the crown of the large cell itself. In the simpler type there is no distinction into superficial and median cells, nor any great concentric stolons above or below, the connect- ing pores being placed about the middle of the large cells, which are often bent in shape. (See figures 4, 5, 7, in plate 5 of Dr. Car- penter's paper.) In the Orbitolites of the Paris basin there is not that clear separa- tion of the superficial from the columnar cells which exists in the other form ; — the upper or outer cells being in fact the upward or downward continuation of the columns themselves, and only sepa- rated from them by the large stolons before described. (See his plate G, figs. 10, 11.) RcceiHaculites. — In the possession of great columnar cells, with large connecting stolons above and below, and with several smaller ones on the sides of the columnar cells, our fossil agrees with the complex forms described by Dr. Carpenter, but (as in the Parisian CANADIAN FOSSILS. 45 Orbkolkes), there are no superficial cells proper, although the cavity has swelled out and been extended at the terminations of the columns above and below, so as to give the appearance of a superficial stra- tum. It will be seen by the description that this form most nearly illustrates our fossil. R. OCCIDENTALIS, N. Sp. Plate X. Figs. 1-7. Synonym.— R. Ncptunii? Hall, Palaeontology of New York, vol. i., page 68, plate 24, figure 3. Specific character. — R. ma gnus, 5-^,pollicaris, vix infundibulatus, crassns, ccllulis vcrticalihus rcclis cylindricis, apicihis siipra rotundatis convcxis, snbtcr planis, rhomboideis grannlatis. Discoid, from four to six inches broad, and from half an inch to an inch in thickness ; the limb gently convex above, but rather sud- denly indented and cup-shaped in the middle, from which the rows of cells radiate in curved lines, crossing like the engine-turned orna. ment of a watch. The thickness of the disk near the centre is hue little, but this increases rapidly towards the margin, becoming in some cases half an inch thick at twice that distance from the centre. The cavities of the cells themselves (in the fossil filled up with silex) are not above a line and a half broad in the largest specimens. They are rhomboidal on the lower surface (figure 5) ; on the upper (fitrure 3) they terminate in a convex boss and have wide openings between, but are ccnnccted by four lateral processes with the adjoining cells. A cross section, as in the right-hand portion of fig. 1 (fig. 6c) shews the columns round {a) and with interstices nearly equal to their own diameter, and a lateral view (figure 6) shews the columns with their bases (a) expanded, so as to leave but narrow linear interstices on the lower s"rface*. At a short distance above this they give birth to four connecting processes or stolons (c), as above described. Tlie columns are thence cylindrical, and nearly their own diameter apart. In one of the specimens there are several intermediate small connecting stolons along the columns (figure 4o), and this is impor- tant in comparing the fossil with the recent Orbitolites. • Figures 1, 4, 5, 6, 1, are reversed, being placed upside down on the plate. Figures 2, 3, shew the upper surface of the cup. »J 1? il. 4G CANADIAN FOSSILS. I . I Miiii • I The upper terminuiion of the cells (fig. Gc) again expands, so as to form broad and closely placed tesserje, with only small cavities between them. These were of course, if the fossil be a Foraminifer, filled up with solid calcareous matter, now removed. One character in particular which tierves to connect the fossil with its living analogue is the very considerable space occupied by the animal matter — now solid spaces filled with silex — both on the upper and lower surfaces. It forms, as above noted, rhomboidal plates on the lower surfaces, which plates are somewhat imbricated ; and the concavities within them (not distinct cells, as in compound Orbitolites,) communicate with each other at one or more of the angles (figure 7) very much in the way shewn by a section of Orbitolites (see Carpenter, 1. c, plate 6, figs. 1, 2), while the intervening calcareous walls are linear and thin. (Sometimes, as in R. mistralis, figs. 8, 9, these basal plates are lobed.) If, instead of comparing Receptaculites with the Orbitolites, wo should suppose it related to any of the millepore corals, or still mure probably to such a form as that of the purple organ-coral {Tulipora tmisica), the reverse of all this would be the case. There should be a calcareous plate or epitheca on the lower surface, from which the tubular corallites would spring, and the walls of these latter, however thin, ought to be visible in the transverse section, which we do not find to be the case in slices of the columns viewed by transmitted light. Again, th'^ upper extremity of the tubes should be open, not closed by convex plates as in the fossil, since such could only be the case when the walls of the coral-cells were so greatly thickened as nearly to close the mouth, while we have seen that in the fossil the corresponding part expands, and is covered over by a definite and often lobed plate, to all appearance continuous with the walls of the cells. If any analogy be suspected between Receptaculites and such Palaeozoic corals as Halysites (the chain-coral), or with Syringopora, there should, besides the characters above mentioned, be indications of transverse plates which have never yet Of peared. I believe all this applies equally to the Receptaculites Ncptuid of the Devonian rocks of Belgium, but there is some appearance of a thin investment of the columns in transverse sections of that species which requires further investigation. And as it is of a deeply infundibuliform shape, there is of course a possibility that it and the other Receptaculites may be very regularly formed sponges ; but I CANADIAN FOSSILS. 4T have the greater satisfaction in the above view of the affinity, because, on explaining the specimf s to Dr. Carpenter, I found that he entirely agreed in it. After pointing out several objections that might bo made, he shewed me that there was in nearly every point J, close coincidence in essential structure between Receptaculites and Orbitolites, the difference being only in the giant size of the cells in this the most ancient of Foraminifera. Localitij. — Plentiful in the limestone of Pauquette's rapids. The Corals and Crinoidea which accompany it are: Pefraia (2 species), Favosites hjcojmditcs (?) or hjcopcrdon, with the Crinoid Schizocrinus nodosus, and a species of GhjptoajstUes, the latter more rarely. R. AUSTRALIS, N. Sp. Plate X. Figure 8-10. Specific character. — R. macrnus^ expaimis, cellulis vcrticalibus subcijlindri- cis incrassatis, ajiicibus subter converts, lobulatls. Under this name a curious species of the genus is figured, for the sake of comparison, from the Silurian limestones of New South Wales. Communicated by the Rev. W. B. Clarke. It is remarkable as having the expanded apices of the columns on the lower surface lobulated in larger or smaller divisions, vhich all seem to radiate from a central boss. And this arrangement is quite different from the merely granulated surface observable in the R. occidcntalis (figure G). The upper surface too (figured as the lower in the plate, figure 8), is curiously lobed beneath the surface. Figure 10 represents a portion of two columns, broken off near the base, and viewed from within. Locality. — Upper Silurian limestona of Yarradong, between the Yass plains and the Murrumbidgee rive". New South Wales, a locality rich in Upper Silurian forms, Tentaculites, Favosites, Pentamerus, Ormoceras, Trochonema, Rhynchonella, &c. J. W. SALTER. February 28tli, 1859. ;i ip CS««(!l)IC,(iD>'5^j:vU;SaL i-^TJIK^TOTiT ODIF O^^^^J^. DECADE 1 Fl 1 LOWER .^lUlKIAN . t / ^ / / # , / , ,t r,i >: ,t . '■ v.'<^"rv s"' V PUITE I. m Maclurea Logani (page 7). Figure 1. Maclurea Logani. Natural size. Lower or umbilical surface. " 2. A younger specimen, with the operculum in place. " 3. Upper view nf uao B|iocimen, shewing the false umbilicus or concealed spire. Thib specimen has suffered some injury, and has* j|««9 concentric furrow. ' ' . ' «! ' • " 4, 5, 6. Extwii^ kMMe and lateral views of an old operculum, with the Apophyses for muscular attachments, a, b. "• I !•■■.*« I I ,1' 'i .^sKdMismKLiA^: s">'i3r:ry:syr m? 'C£^.&:idjl DECADE !. PI 2. lOV/EK SlLTIRuI'l (Trenlonl 9 .r-1-*^ '/&;^. )-<. j-' f 7 /j /:' ■■■•-•.I ^^ #' ^<^V>^' V t^ll-l, y-//. ,■.'.,//.' J.ir' ' ■!■' ''"•'''■ ii: c' U ihiiiiihl I Ih I // /; // PLJTE II. Raphistoma lavicida (page 12). Figure 1. Raphistoma lapicida. Side view, with mouth. " 2. . Spire of ditto. " 3. . Base of ditto. Raphistoma aperta (page 12). " 4. Ruphtdoma aperta. Upper, lower and side view. ■i m liLLicoTOMA planulata (page 14). " 5. Helkotoma planulata. View of the spire. " 6. . Same specimen ; under view. " 7. . Do. side view. " 8. . Vai-, muricata. Helicotoma ? SPINOSA (page 15). " 9. Helicotoma ? spinosa. Slightly magnified ; the natural size is indicated by the cross lines. " 10. Under view of the same, also magnified. Helicotoma lauvata (page 15). " 11-13. Helicotoma/ larvata. Upper, under and side views. " 14. . The same species, encrusted by a sponge (Stromatocerium. rugosum). \m I v':t ^^a.ziAiKcij,^:. £:Tr:Y.7:gT ...:■.' (fu.Kfi*.i'>.i\, DV.:.t\3K : p; ?-. T.OWKR i.:i.URI/VV. {( i^lliTOi'S Sand Hocir I ■I' 'j I I O' / ■Ni 'ST.^^'."^!^. . ■>r/,^ W :. w-i-b. v.'.ADK : PI ?.. U'KR f.n.URLVN. iliTiiiitiSanci Horki PLJTE III. Ophileta compacta (page IG). Figure 1. Ophileta compacta. Internal sandstone cast ; only a portion of one whorl is left. Internal cast, sandstone, re •^rsed, and shewing the flat or umbilical surface, c, the inner ba. angle; 6, the outer basal angle ; a, the upper angle or keel. The convex dome-like cast of the deep cup-shaped spire shews distinctly, as the whorle are broken away. " 2. Cast of lower or umbilical surface. 3. Exterior of upper or concave side, a, the outer angle or keel ; d, the inner upper angle. A gutta-percha mould, taken from a cast of the upper surface, reprcsea ing therefore the true shell. ' t 1- ' (' i .-rb- r'l ' III J ;< i f ';nssji)x.©(&Ji(C^uii :3i3"Si\riS«' mr 'rj«\.sy.*^iBi\.. LOWl'.P SUJil'LAil (Tre-ntoii ) ' m> ]!:/r,:/il orihi :urnil{iLi. ./,//. 2 •/-'//. ////•//.. -•/,/. ^'.,// M iir I'ini /I ji/l .'/f,/ . .■{ ////„ PLjiTE IV. feN MURCHISONIA SEUKULATA (page 20). (Not aerra tu, as in page 80.) Figure 1. Murchuonia ierrulata. Natural size ; 1», a portion magnified. MURCHISONIA HELICTERE8 (page 21). 2. mrchuoniahelicteres. A normal specimen. " 3, 3a, 4. TK . The same species, Irregularly uncoiled. The sutural edge on the uncoiled whorl is indicated at s. I'M MuiiCHISONlA BICINCTA (page 19). •' 0, «. Munhisonia bicincta, Hall. Ordinary large variety. ~~" ' -• ^''^'"^y with more angular whorls, and w.thou- the upper keel. (Var. perangulata, Hall.) hv !S\ W- Vy "iiiKctiiriCwaax.auaii t^T[L'ii'.\7/7F,T!; roi;?' ff?.i\]a*j5^j5:. . '1-1' LCWTR 5ILi:£aA>: f Trenton ) ' ' ■'Xk mMiX}-.- ^W^K if. ' ]n ^ J 1,1 I \f I. /;■/"■, /,',,■ //•//,/// '/., If /// /I , .jiw'i-b'/ i;k 1 PI ;. J . hi Its s PL..1TE V. • MURCIIISONIA UUACILIS (page 22). Figure 1. Murchisonia gracilis, Hall. The cast or body-whorl a good deal broken aw.y, and shewing the inner reflected lip. " \a. An enlarged whorl, to shew the lines of growth and the smooth band. Murchisonia ventricosa (page 23). 2. M. ventricosa, Hall. Of large size. The body-whorl here is also broken away; hence the pillar-lip, p, and the base of the whorl, b, are more prominent and curved than they should be. At s a slight ridge, just above the suture, is sometimes visible. 2a. Shews the moderately arched lines of growth. 3. A smaller specimen, less elongate than usual. The position of the band high up, near the sutures, is contrasted in this species with that of ilf. gracilis, figure 1. J"i 'I' lir I ('•i-b7 -'(I: fill' It ^' u :-xm'.,^^?r2CA7u Mi'MyT)^ -»yc' ":i\:itiAii".a. LuWKF ;. LOXONEMA MUKUAVANA (page 31). " tJ. Lo^onema Murrayana. Au uni,ue sj^-nmeu, LnbcMdcd in limestoue. 11 M ^■i '! ( { I i ^n: Ik, 1 (6E(&IL.®(&3I(CiUL S■llra'.^^ET ©IF C^JflilBA DECADi: I PI 7 LOWER SILURIAir I Trent on ■ II '^■i J: I ! • ! I- . rf If: V V t ,_^' F I r Is*:" Pf "^^ •J- ( f //^/. / i.(\i-li'r /■:!.■< !'ii!:r. '-"<:,,■/.,■.,., :/ n _, J-:,'f-,i,fSK /,,.'/■ C'.nf. ih. .; ..,*..!iy ILURIAir ton I PLJTE VIL I . (' CyrtOoERas falx (page 32). Figure 1, Cyrtoceraa falx, Billings. Side view and section of the larger end, the siphon on the outer (ventral) side of the curve. 2. Section (with siphuncle) of a more compressed form, the compres- sion partly due to pressure. The tube becomes more and more cylindrical in age. " 3, 3a. A younger specimen, from the Ottawa limestone. 4. A worn specimen, shewing the close septa. Cyrtoceras Billingsii (page 33). 6. Cyrtoceras Billinssii (C. lamdlosum, Hall). Side view. 5» is the section at the larger end ; 5»» of the smaller cylindrical end— the siphon external. C. A younger specimen, with closer lamella} of growth. '' \ . , , p, f li ' [<• -' l.v,: lift iCdi'IL'iDt&IIi.ailui fflTIEKffJE'iT (f'Jf' (f.i'J2rA\:iliiV DECADE 1 M a r.owrK i. it.in ixn ■>,i .rrioVTr^uZ^ ^K VJ^'^T?^':^ lTI '^ ^ '/.; \ \\\ m I I! i C 5. £one i'l" ,'/.,'•/. .'' '' ' ri'/i I fill-tit -^/A-, A' III /■>''>•'//, I ,.,' 7. (' ',;.^.'.;r/,i/; mi/.: ,./ 7 M 8 Un IAN on ; ► fLATIi VIII Ctknodonta nasuta (pag«' iiij). Figure 1. Ctenodonta nasulu, UnYl, Natural size. " 2. , — . Largo apeciraen, with external ligament and liinge-teeth. , ► Ctenodonta Logani (page 30). " 3. Ctenodonta Logani. Interior of left valve. 3a, the hinge enlarged. Ctenodonta contracta (page 37). " 4. Ctenodonta contracta. Var. with posterior sinus well marked. 4a, enlarged, to shew ligament. " 5. The same, with the sinus obsolete. 5a, the hinge enlarged, the muscular impressions deep. 'J H (I f Ctenodonta gibberula (page 38). " G. Ctenodonta sibberula. Interior and exterior of the left valve. Ctenodonta ASTARTiEFORMis (page 39). " 7. Ctenodonta? astartaformis. Left valve, outside and interior, la, the hinpe-line magnified. ! fl| "! I 'if llV IC^ l!.' '/I I I li. I AH: m «?r;r,a\i::,:m ' '',/.',/ As i '. 1 PIK triTi ) PL^TE X. ^ > Reckptaculites occidextalis (page 45). Figure 1. lieccptaculitcs occidentalis. Upper view of a fragracnt of a large speciruon. At a, a, rubbed portion exposes sections of the cylindrical columns. :;. A more weathered specimen, upper side shewing the convex ends of the columns. " 3. Cupped central part of a specimen. " 4, 5. Detached fragments reversed, the upper side downwards, shewing the rhomboidal bases to the columns, ia ditto,, shewing the connecting stolons. -iL, tlie same magnified. '■ (>. (.)ne or two columns magnified, reversed, a, the rhomboidal gran- ulated space ; b, the connecting basal stolons ; c, the apices of the columns ; rf. the interstices between them ; <>• i? the base of one of tlie columns, more highly magnified. " 1. Sliews a portion of the lower surface polislKMl. Some of the rhomboidal .=paccs are connected by the stolons with each other. 'H?/' ?• Keckptaculites ArsTRALii^ (page 47). 8. Rcceptaculites australis, Salter. A new Australian species, intro- duced for comparison. Lower surface, with the lobed bases of iho columns. 9. Some of the cnhimns magnified. Tlie stolons arc not clearly seen in this specimen. 10. View from the inner surface of those lobed bases, shewing the ramifications of the sarcode highly magnified. ■'i t