GN 
 
 130 
 
 E7
 
 ( LIBRARY^ 
 
 UMVRWTY"e 
 CALIFORNIA 
 
 1 SAN DIEGO I
 
 Dcpnrlnicnt of 3Uiiics 
 
 Hon. LOUIS CODERRE, Minister; 
 R. G. McCONNELL, Deputy Minister. 
 
 Oteolagicnl Sttrucu 
 
 Museum Bulletin No. 9 
 
 ANTHROPOLOGICAL SERIES, No. 4. 
 
 MARCH 6, 1915 
 
 THE GLENOID FOSSA IN THE SKULL 
 OF THE ESKIMO 
 
 by 
 
 F. H. S. Knowles f 
 
 OTTAWA 
 
 GOVERNMENT PRINTING BUREAU 
 1915 
 
 No. 1492
 
 LIBRARY 
 
 UNIVERWTY OF 
 CALIFORNIA 
 
 SAN DIEGO
 
 THE UNIVERSITY LIBRARY 
 
 UNIVERSITY OF CALIFORNIA, SAN DIEGO 
 
 LA JOLLA. CALIFORNIA 
 
 March 6, 1915 
 
 Canada 
 
 Geological Survey 
 Museum Bulletin No. 9. 
 
 ANTHROPOLOGICAL SERIES, NO. 4. 
 
 The Glenoid Fossa in the Skull of the Eskimo. 
 By F. H. S. KNOWLES. 
 
 The glenoid fossae in the human skull are concave depres- 
 sions on the basal aspect of the temporal bones. Each fossa 
 is divided into two parts by the Glaserian fissure; the anterior 
 portion concave, smooth, and bounded in front by the eminentia 
 articularis, serves for the articulation of the condyle of the lower 
 jaw; the posterior portion, rough and bounded behind by the 
 tympanic plate, serves for the reception of part of the parotid 
 gland. It is with the anterior portion that I intend to deal, 
 and my object in this paper is to show that in the skulls of those 
 Eskimo who have existed under the primitive conditions of life 
 habitual to their race, the surface for articulation with the man- 
 dible is not deeply concave as in the skulls of modern highly 
 civilized races, but tends on the whole to be shallow, and in 
 many instances very remarkably so. I have examined numbers 
 of skulls belonging to various primitive races and in many of them 
 one can pick out crania presenting flattening of this fossa in a 
 more or less marked degree. W. L. H. Duckworth in his "Studies 
 in Anthropology," page 107, notes in his description of some 
 aboriginal Australian crania in the Cambridge University 
 Museum: "It is here to be remarked that the glenoid fossae 
 of this specimen (No. 2137) are very shallow and flattened, 
 the flattening being most pronounced in the region of the an- 
 
 136 

 
 2 MUSEUM BULLETIN NO. 9. 
 
 terior border of the cavity so that the anterior root of the zygoma 
 is indistinct. It is submitted that such a shallow glenoid fossa 
 is an approach to a state that is usual in anthropoid apes ; (among 
 Australian crania Nos. 2138, 2139, 2140, exhibit the same feature 
 in a less marked degree)." I myself have noted this glenoid 
 flattening, exemplified in a most remarkable manner, in some 
 New Caledonian crania belonging to the Williamson collection 
 in the Museum of the Royal Army Medical college, London; 
 indeed, it was during an examination of these crania that my 
 attention was first called to this peculiarity. I have also 
 noted this condition in the skulls of other races living under 
 primitive conditions, but in most of them it would seem to be 
 probably a local and no doubt in some cases an individual 
 characteristic; one can, for example, find many Australian 
 crania with deep, well marked, glenoid fossae and the same 
 remark applies to other races. When, however, one examines 
 a series of Eskimo skulls, one is at once struck by the almost 
 uniformly shallow appearance of these fossae; it seems, indeed, 
 to be the exception to find in an Eskimo skull a very concave 
 glenoid fossa, whilst many of them present an extreme appear- 
 ance of glenoid flattening. 
 
 When an examination is made of the glenoid fossa in any 
 skull which exhibits this shallow form, it becomes evident that 
 this appearance is due most largely to the rolling and flattening 
 out in the forward and outward direction of the eminentia 
 articularis, as well as perhaps to a relatively lesser depth of fossa. 
 Hence, in extreme cases, such as in figure 3, Plate II, the emin- 
 entia articularis merges into the fossa in a continuous straight 
 line, while the fossa itself is wide and shallow. In intermediate 
 forms, such as figure 6, Plate II, the eminentia, although con- 
 siderably flattened, yet is still slightly curved, while the 'anterior 
 concave portion' of the fossa can now be recognized. The 
 glenoid fossa in the skulls of modern civilized man, presents a 
 very different appearance to this: the eminentia is high and 
 prominent, while the concave portion is deep and very clearly 
 defined. See diagram, Plate I, and figures 1 and 2, Plate II. 
 
 Now C. S. Tomes, in his "Dental Anatomy," points out 
 the influence of different methods of mastication upon the form
 
 THE GLENOID FOSSA IN THE SKULL OF THE ESKIMO. 3 
 
 of the glenoid cavity ; he writes: "The form of the glenoid cavity 
 .... bears an intimate relation to the dentition of the animal 
 and the nature and extent of the movement of the jaws. Thus 
 in a child it is nearly flat with no well marked surrounding ele- 
 vations, its axis is transverse and little rotary motion is made 
 use of. In the adult it is deeply sunk, the axis of the condyle 
 is oblique and rotary movements are largely made use of in 
 triturating food. In the felidae it is strictly transverse, their 
 teeth adapted for slicing but not grinding, would gain nothing 
 by lateral motion, which is rendered quite impossible by the 
 manner in which the long transverse condyles are locked into the 
 glenoid cavity by strong processes in front and behind . . in 
 Herbivora the condyle is roundish, the ascending ramus long, 
 the pterygoid muscles large and the glenoid cavity shallow. 
 In the whale, which of course does not masticate at all . . the 
 articulation is reduced to a mere ligamentous attachment." 
 Here, then, I think we have the key to our problem, and that 
 we shall find that it is to some differences in the method and ex- 
 tent of mastication that is due the distinction in the form of the 
 glenoid fossae between civilized and primitive man. Since, 
 therefore, in the Eskimo we have a race which seems most 
 uniform in the display of glenoid flattening, we will take them 
 as the champions of the "shallow-glenoid" type, and examine, 
 first, the conditions of their life and the nature of the food they 
 have to masticate, and, secondly, the form of the masticatory 
 apparatus presented in their skulls. 
 
 Now it is well known that the staple diet of the Eskimo is 
 of a more or less purely animal nature, fish, flesh, and fowl being 
 their main means of subsistence, while, to judge from all accounts, 
 much of the meat they eat must be of a very tough nature; 
 so that, on the whole, we could not find any other race of the pres- 
 ent day in which there would be so much need for strong jaws, 
 and so much need too to use them in such a manner that their 
 food should be thoroughly triturated before being swallowed. 
 A few extracts from the writings of authors who have lived 
 among and studied the Eskimos will perhaps be of use to em- 
 phasize my point, and give confirmation to my statement as 
 to the nature of the Eskimo's food.
 
 4 MUSEUM BULLETIN NO. 9. 
 
 Fridtjof Nansen in his "Eskimo Life" writes: "Meat and 
 fish are eaten sometimes raw and frozen, sometimes boiled, 
 sometimes dried .... Among other dainties I must mention 
 the skin (matak) of different sorts of whales, especially of the 
 white whale and porpoise, which is regarded as the acme of 
 deliciousness. The skin is taken off with the layer of blubber 
 next to it, and is eaten raw without further ceremony . . the 
 skin is as tough as India-rubber to masticate, so that the enjoy- 
 ment can be protracted to any extent . . A delicate dish which 
 does not however rival matak, is raw halibut skin. It has the 
 advantage that, by reason of its toughness, it goes such a long 
 way . . ." "The Greenlander is also very fond of raw seal 
 skin with the blubber." In another place again in describing 
 their physical characteristics he writes: "He has a . . broad 
 mouth; heavy, broad jaws; which, together with the round cheeks, 
 give the lower part of the face a great preponderance in the 
 physiognomy. When the mouth is drawn up in an oleaginous 
 smile two rows of strong white teeth reveal themselves. One 
 receives the impression, upon the whole, of an admirable chewing 
 
 apparatus " Another author, Mr. H. Whitney 1 , relating 
 
 his experiences among the Highland or Northernmost Eskimos, 
 writes: "While Eskimos eat much of their meat raw and relish 
 it so, they prefer it cooked when conditions permit of cooking. 
 It can be understood how difficult it is to cook it when it is 
 remembered that the only fire they possess is the one supplied 
 by the stone lamps." "The skins (of the little auk) are first 
 thoroughly dried, then the women chew the flesh side until all 
 oil is extracted and the skin is soft and pliable and ready 
 to be sewn into the garment with sinew. In preparing seal 
 and other skins for sewing the women always resort to the chew- 
 ing process." "The main feature of the feast was an uncooked 
 meal." " They get sustenance too by eating hard frozen raw 
 walrus and seal meat or blubber." " A stone lamp was set up, 
 but the seal blubber frozen hard had to be thawed before it 
 could be burned. This was done by the Eskimos chewing 
 and spitting it when softened, into the lamp." "Even little 
 
 J See "Hunting with the Eskimos," by H. Whitney.
 
 THE GLENOID FOSSA IN THE SKULL OF THE ESKIMO. 5 
 
 youngsters, some of them not yet over three years of age 
 chewed the dripping meat and blubber." (This meat and blub- 
 ber was raw and the author was there describing the scene of 
 feasting after the killing of some seals). Lastly, "Very small 
 tots might be seen at any time chewing pieces of raw seal or 
 walrus meat." 
 
 This will be enough to show the nature of the food of these 
 people and how very essential it must be for them to be provided 
 with strong jaws and with biting and chewing muscles corres- 
 pondingly large and powerful. When we examine a series of 
 skulls of adult Eskimo, we have ample evidence that our 
 conclusions from the nature of their food, are borne out 
 by the form of their jaws and the muscle attachments 
 on their skulls. An Eskimo's jaws are essentially of a biting 
 and chewing type. The extent for the attachment of the tem- 
 poral muscles on the sides of the skull is very great, being on the 
 whole more marked in the skulls of this race than in 
 any other of the existing races of man. The external pterygoid 
 plates are large; this is noted in a paper by J. Brierley and F. 
 G. Parsons. 1 "The external pterygoid plate is very broad 
 antero-posteriorly. This is probably due to the development of 
 the pterygoid muscles." This is important since the external 
 pterygoid muscles are the chief agents in the lateral movements 
 of the mandible and, as I shall endeavour to show, it is just 
 this lateral triturating movement when practised early and 
 extensively, that is of importance in its flattening effect on the 
 glenoid fossa. The zygomatic arches and malar bones are large 
 and projecting. Especially is the form of the mandible note- 
 worthy (see Plate III); the ascending ramus is low, broad, and 
 strong, the area for insertion of the masseter and pterygoid 
 muscles being well marked and very extensive. Now the super- 
 ficial portion of the masseter muscle assists the external pterygoid 
 in drawing the lower jaw forward upon the upper, the jaw being 
 drawn back again by the deep fibres of the masseter and posterior 
 fibres of the temporal. The marked development of the mas- 
 seter and the posterior fibres of the temporal muscles in the 
 
 1 See "Notes on a Collection of Ancient Eskimo Skulls," Journ. Anthr. 
 Inst., 1906.
 
 6 MUSEUM BULLETIN NO. 9. 
 
 skulls of these people is, therefore, further evidence of the 
 activity and extensive movements of their mandibles during 
 the process of mastication. Lastly, the coronoid process is 
 low and very stout, and its distance from the condyle renders 
 the leverage of the temporal muscle on the mandible still more 
 effective. 1 
 
 Dr. Ales Hrdlicka 2 remarks upon the great development 
 of the jaw muscles in the skulls of the Eskimo, with especial 
 reference to the size and strength of the temporal muscles and 
 their probable effect upon the shape of the skull. He also notes 
 the great breadth of the ascending ramus of the mandible, strong 
 coronoid process, and, in certain of the lower jaws examined 
 by him, "remarkable individual variations, due to a great 
 development and activity of the masseter muscles." From 
 this very instructive paper I will quote the following paragraph 
 (page 211), as it is of exceptional interest in the present 
 connexion : 
 
 "The lower jaw presents a moderate to fairly prominent, 
 and not rarely square chin, medium height, very strong build, 
 and broad ascending branches. A marked and general feature 
 is a pronounced bony reinforcement of the alveolar arch extend- 
 ing above the mylo-hyoid line from the canines or first bicuspids 
 to or near the last molars. This physiological hyperostosis 
 presents a more or less irregular surface and is undoubtedly 
 of functional origin, the result of extraordinary pressure along 
 the line of teeth most concerned in chewing, yet its occurrence 
 in infant skulls indicates that at least to some extent the feature 
 is already hereditary in these Eskimos." 
 
 When we turn to the shape of the palate we find still more 
 evidence, both as to the severe nature of the work which the 
 jaws are called upon to perform, and also the chewing method 
 which has evidently been of most service in its accomplishment. 
 
 1 See "A consideration of some of the more important factors concerned 
 in the production of man's cranial form," by Prof. A. Thomson, Journ. Anthr. 
 Inst., 1903. 
 
 2 See "Contribution to the Anthropology of Central and Smith Sound 
 Eskimo," American Museum of Natural History, Vol. 5, Pt. 2. (Anthro- 
 pological paper).
 
 THE GLENOID FOSSA IN THE SKULL OF THE ESKIMO. 7 
 
 Here, however, it will be necessary to make a slight digression, 
 as some views of Dr. Keith 1 help to throw much lighten the pres- 
 ent investigation. He remarks that in all anthropoid forms, 
 both recent and extinct, the canine teeth are so developed that 
 a side to side grinding movement in mastication is impossible; 
 that the canine teeth are developed to prevent such a movement, 
 and that they serve as guides to prevent the jaws from "skidding" 
 or slipping when brought forcibly into action; that in crushing 
 their food, the lower teeth ascend more or less forcibly against 
 the upper. 
 
 Dr. Keith then goes on to show that in Mousterian man 
 the form of the palate had far departed from the anthropoid 
 type, and that this departure, made possible by the subsidence 
 of the canine teeth to the level of their neighbours, was due to 
 the evolution of a new form of mastication, namely, a side-to- 
 side chewing movement. Now the palate of Mousterian man 
 was remarkable for its horseshoe shape and its relatively great 
 width, while the dental roots of the Mousterian race were highly 
 specialized. The roots of the teeth from St. Brelade bay, 
 Jersey, were remarkable for their fusion due to the great hyper- 
 trophy of their dentine and cementum and, as Dr. Keith has 
 pointed out, it seems clear that these features were due to the 
 side-to-side grinding movement in mastication, "the fusion of 
 the roots being a result of overgrowth to withstand the great 
 lateral strain thrown on the teeth in a side to side mastication," 
 whilst "the great width of the palate was also due to the pre- 
 ponderance of the side to side movement." .... "In modern 
 races," on the other hand, "especially highly civilized races, 
 a modified form of the anthropoid bite has reasserted itself. 
 In place of the canines serving as guides to prevent a side to 
 side movement the lower incisors bite and pass upwards behind 
 the upper ; the incisor teeth serve to insure a vertical and scissor- 
 like action of the teeth. With the evolution of the modern and 
 overlapping bite and diminution of the side-to-side movement 
 there is a tendency to narrowing of the palate." 
 
 1 See a description of teeth of palaeolithic man from Jersey by A. Keith 
 and F. H. S. Knowles, Journ. Anat. and Phys., Vol. 46.
 
 8 MUSEUM BULLETIN NO. 9. 
 
 I have quoted Dr. Keith's views at some length, for I think 
 that it is by reference to a strongly developed side-to-side 
 movement of the mandible in mastication that we can explain 
 the shallowness of the glenoid fossa in the Eskimo, while to the 
 diminution of this movement, the deep fossa in modern man 
 may be attributed. In the matter of diet, the conditions under 
 which Mousterian man lived were much the same as for the 
 Eskimo of the present day. He was essentially a hunter and 
 subsisted mainly on the flesh of animals killed by him, and it 
 must have been very often tough flesh too, if one may judge 
 from the bones left as evidence of his feasts; cave-bear, wild 
 horse, reindeer, mammoth, rhinoceros, and bison, seem to have 
 been represented among his foods 1 , while we have no reason to 
 believe that his cookery was of anything but an exceedingly 
 primitive nature. Should further evidence be needed, we have 
 it in his enormously powerful jaws and the correspondingly 
 extensive muscular impressions upon his skull. If, therefore, 
 Mousterian man found it necessary to specialize in this side-to- 
 side masticatory movement of the jaws in order to cope with 
 the tough nature of his food, and seeing that it had also had this 
 secondary effect upon the form of his palate and the roots of 
 his teeth, we shall not be surprised, I think, to find evidence 
 of the same masticatory method, accompanied by its secondary 
 effects, in the skull of the Eskimo. We have already seen from 
 our inquiry into the diet of these people that their ordinary 
 food is of such a nature as to need a most thorough and work- 
 manlike chew. That this chewing is carried out by means 
 of an extensive side-to-side movement of the mandible we find, 
 I think, fully illustrated in the form of their palates and teeth. 
 This completes the evidence already derived from an inspection 
 of the muscular attachment on their skulls and the form and build 
 of their lower jaws. 
 
 Their palates are broad and of the horseshoe shape typical 
 of the Mousterian palatal form. The measurements of five 
 very large Eskimo palates give an average palato-maxillary 
 length of 55 m.m. and breadth of 71 m.m. This will show the 
 
 1 See "Ancient Hunters, "by Prof. W. J. Sollas.
 
 THE GLENOID FOSSA IN THE SKULL OF THE ESKIMO. 9 
 
 great width of these palates, as compared with their length. 
 (The palato-maxillary length in these cases has been measured 
 from the mid-point of a line drawn across the hinder borders of 
 the maxillary bones, to a point between the anterior margins of the 
 central incisors ; hence this measurement is not strictly comparable 
 with those given by Dr. Keith as the measurements for the 
 Heidelberg, Gibraltar, and Jersey specimens). The form of 
 the palate in the Eskimo skull No. 1 illustrated here (see Plate IV), 
 is very typical of this horseshoe shape, and is very similar 
 to the palatal shape of the Gibraltar skull. As we have already 
 seen, the biting and chewing muscles are all in a high state of 
 development in the Eskimo skulls, while the external pterygoid 
 plates are noticeably large. Now the external pterygoid muscles 
 are the direct agents in the side-to-side grinding movement. 
 If the muscles on one side act, the corresponding side of the jaw 
 is drawn forward, and the other condyle remaining comparatively 
 fixed, the symphysis deviates to the opposite side. The alter- 
 nation of these movements on the two sides produces trituration. 
 When we turn to the teeth, although the roots do not show that 
 degree of specialization to which those of Mousterian man had 
 arrived, yet the form which the wearing down of their crowns 
 takes is very noteworthy. All the teeth are in the adult very 
 much worn down by attrition, the incisors and canines just as 
 much as, and sometimes even more than, the others. This 
 appearance is due to the fact that in this race, as indeed is the 
 general rule among all races living under primitive conditions 
 of food and cookery, the lower incisors are in apposition to those 
 in the upper jaw and do not, as in civilized races, bite behind 
 them. 1 Hence, in a side-to-side grinding movement of the 
 mandible, accompanied, as it will necessarily be, by antero- 
 posterior movements as well, the surface of the incisors would 
 play over each other to the same extent as those of the molars; 
 in addition to which must be taken into consideration also the 
 wear occasioned by the meeting of these teeth in biting move- 
 ments of the jaws. 
 
 1 See "Craniology of Australians with reference to dentary arcade," 
 by Sir William Turner, Journ. Anat. and Phys., 1891.
 
 10 MUSEUM BULLETIN NO. 9. 
 
 The molar and bicuspid teeth in many instances present 
 a very remarkable appearance. This is, in the case of the upper 
 set, evidence of wear mainly on the lingual side, in the lower, 
 mainly on the labial. Taking, for instance, a first 
 molar that has been in use many years and is much worn 
 down, the resulting shape is very peculiar. In the case of an 
 upper tooth, a sharp high edge is present on the outer or labial 
 margin, while on the lingual or inner margin the worn crown 
 slopes sharply away from this edge, sometimes, indeed, right 
 down to the alveolar border. An opposing lower tooth from 
 such a skull would show a wearing away in exactly an opposite 
 direction, although never to such a pronounced degree as in the 
 upper tooth. Of the molar teeth, the first is usually the most 
 advanced in this condition, the second and third less so, as one 
 proceeds backwards. The second bicuspid also shows a high 
 degree of this oblique wear, the first rather less, the canine 
 scarcely any at all, its worn surface being more or less flat, 
 while the surface of the incisors is usually flattened also. This 
 appearance is not peculiar to the teeth of the Eskimo. I have 
 noted it in certain American Indian skulls in particular, two 
 skulls from the interior of British Columbia and one from 
 Ontario and it is quite possible that it may be found in skulls 
 from other regions or races where local conditions of diet, methods 
 of mastication, and palatal shape, combine to produce conditions 
 similar to those found among the Eskimo. For among the 
 Eskimo this oblique wear of the teeth seems to be of quite 
 common occurrence. It is probably due, I think, to the crushing 
 and grinding chewing movements of their jaws combined with 
 the broad horseshoe palate typical of their race. The deviation 
 forwards and sideways of their mandibles in the process of chew- 
 ing must be extensive and carried out with their biting muscles, 
 powerful as we have seen them to be, in a high state of contrac- 
 tion in order to assist in crushing and grinding the food in pro- 
 cess of mastication. The result probably is that in the forward 
 and sideward movements of the mandible and this more es- 
 pecially in the case of a palate of typical horseshoe form 
 the outer margins of the centre-lateral teeth of the lower set are 
 brought into hard grinding contact with the inner sides of the
 
 THE GLENOID FOSSA IN THE SKULL OF THE ESKIMO. 11 
 
 opposing teeth in the upper jaw, this resulting in an oblique 
 wear to the teeth constituting the central portion of the lateral 
 curve of the palate. 
 
 Again, as in the side-to-side chewing movements of the jaws, 
 it is just these teeth that bear most of the sideways strain, 
 it is only to be expected that a broad horseshoe type of palate 
 should be practically universal in the skulls of this race. More- 
 over, since it is upon the centre-lateral teeth that so much side 
 strain must fall and since the first molar is usually at the centre 
 of the lateral curve, it is interesting to note that in many cases 
 the lingual root of this tooth is very large and divergent, this 
 being evidently an adaptation to the strenuous side-to-side 
 method of mastication and affording a stout, buttress-like 
 support to the tooth in question. In Plate II, figures 1 and 2, 
 the lingual root of the first molar will be seen projecting out 
 into the palate to a remarkable extent. 
 
 From all this evidence that I have been able to adduce, 
 I think it will now be readily granted: 
 
 (1) That the food of the Eskimo is of an extremely tough 
 nature and must need thorough mastication by very strong 
 jaws. 
 
 (2) That these people do indeed possess immensely power- 
 ful jaws, and are from a very early age accustomed to make use 
 of a strongly developed chewing method for the trituration of 
 the tough substances constituting their ordinary diet. 
 
 (3) That not content with the ordinary severe chewing use 
 to which their jaws must be put, they regard as bonne-bouches 
 substances which no ordinary jaws and teeth could make any 
 impression upon; added to which the chewing power of their 
 jaws is, in the case of the women, made use of in the manufacture 
 of their garments from the skins of animals, etc. 
 
 (4) That this chewing is, in the main, a widely extensive 
 side-to-side movement of the mandible and reacts in varying 
 degrees of intensity upon the form of their crania, mandibles, 
 palates, and teeth. 
 
 In conclusion, therefore, I think it probable that we have the 
 following factors to deal with: (1) The free and extensive 
 antero-rotary movements of the condyles necessary in this
 
 12 MUSEUM BULLETIN NO. 9. 
 
 method of mastication, and carried out with the powerful biting 
 muscles in a high state of contraction. (2) The fact that the 
 whole process is begun at a very early age. This second con- 
 sideration is of great importance, as it is in the young growing 
 skull that environmental reactions produce a lasting effect. 
 Finally, the pressure of the condyle on the eminentia articularis 
 has resulted in the prevention of the downward development 
 of the latter, and has rolled and flattened it out in the manner 
 presented to us so frequently in their skulls. 
 
 In the anthropoid ape the glenoid fossa is shallow and the 
 eminentia articularis flattened (see figures 9 and 10, Plate II), 
 but this cannot be put down to a side-to-side movement in masti- 
 cation, as Dr. Keith has pointed out its impossibility in their 
 case; it may possibly be due to the very heavy mandible and, 
 proportionately to the size of the cranium, huge condyles, 
 combined with extensive forward movements of the condyles 
 in opening and closing the mouth and an antero- posterior 
 movement of the same in mastication. 
 
 To sum up, then, in any primitive race where the food is 
 tough, cookery imperfect, and strenuous side-to-side mastication 
 needed, we should, I think, expect to find examples of shallow 
 glenoid fossae, but in none of them would this be so marked or 
 so universal as in a race such as the Eskimo, living almost 
 exclusively upon a diet of tough and poorly cooked flesh. 
 
 In modern highly civilized man, on the other hand, 
 where, owing to the soft well-cooked nature of the food, 
 such strenuous masticatory movements are no longer necessary, 
 a scissor-like snapping action of the teeth being substituted 
 for the vigorous side-to side grind of primitive man, the condyles 
 in the action of trituration need never move far or with great 
 force out of the glenoid fossae; while, owing to the small extent 
 to which the jaws diverge in the act of mastication, and to the 
 absence of any necessity for powerful biting movements, the 
 condyles of the mandible during mastication need never press 
 with that hard rolling action upon the eminentia articularis. 
 Hence in these races we find a deep glenoid fossa and a high and 
 prominent eminentia articularis.
 
 THE GLENOID FOSSA IN THE SKULL OF THE ESKIMO. 13 
 
 We are likely, I think, to find the same condition in any 
 race or section of any race where the food is soft, either owing 
 to its nature or the method by which it is prepared for consump- 
 tion, and this whether the race is ancient or modern, primitive 
 or civilized, white, black, or brown in colour. It seems to be 
 simply a question of diet and cookery. Again, it is likely 
 that even in members of the same race marked differences may 
 be found, due to local conditions of diet, and it is quite probable 
 too that, for instance, members of the same tribe may differ 
 to a certain degree owing to individual characteristics. Still, 
 I think the broad fact remains that in any race or in any ethnic 
 group where the food or method of preparing it is such that 
 strenuous mastication is required, the glenoid fossae of the 
 individuals constituting that race or group will in general display 
 a shallowness not met with amongst peoples enjoying softer 
 conditions of diet.
 
 14 MUSEUM BULLETIN NO. 9. 
 
 REFERENCES TO LITERATURE CONSULTED. 
 
 Gray's Anatomy, descriptive and surgical. 
 
 The Joints of Mammals compared with those of Man, by F. G. 
 
 Parsons, Journ. Anat. and Phys., vol. 34. 
 The Articulations of the Vertebrate Jaw, by H. George F. Spurrell, 
 
 Proc. Zoolog. Soc., Lond., 1906, vol. 1. 
 Studies in Anthropology, by W. L. H. Duckworth. 
 Dental Anatomy, by C. S. Tomes. 
 Notes on a Collection of Ancient Eskimo Skulls, by J. Brierley 
 
 and F. G. Parsons, Journ. Anthr. Inst., 1906. 
 A Consideration of some of the more important factors concerned 
 
 in the production of Man's Cranial Form, by Prof. A. Thom- 
 son, Journ. Anthr. Inst., 1903. 
 Contribution to the Anthropology of the Central and Smith Sound 
 
 Eskimo, by Ales Hrdlicka, Amer. Museum of Nat. Hist., 
 
 vol. 5, pt. 2. 
 A description of the teeth of Palceolithic Man from Jersey, by A. 
 
 Keith and F. H. S. Knowles, Journ. Anat. and Phys., 
 
 vol. 46. 
 
 Ancient Hunters, by Prof. W. J. Sollas. 
 Craniology of Australians with reference to dentary arcade, by Sir 
 
 William Turner, Journ. Anat. and Phys., 1891. 
 Eskimo Life, by Fridtjof Nansen. 
 Hunting with the Eskimos, by H. Whitney. 
 
 ACKNOWLEDGMENTS. 
 
 For the photographs in Plates III and IV and for material 
 made use of in preparing the sections illustrating Plates I and 
 II, I am indebted to the courtesy and kindness of Dr. Arthur 
 Thomson, Professor of Human Anatomy of Oxford University. 
 The specimens illustrated are in the cranial collection of the 
 Oxford University Museum.
 
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 ffiioqrrtsj lo noi^ioq guonjaT = 1 
 maJ lo nomoq ?.uofnBup8 = 2 
 
 arfJ lo tlsl grit ot slltil anslq IfiWrssS aril ni HJJ esw noitosa 3yods sriT 
 nwBib 3mji8ib ari} ntBlqxs Iliw jl .siuaaft nshaaBN) ariJ lo nsq 
 , 9itsft nrnworie auaeo'l bionaft) euoht,/ i ?Rfco srij "to snoboaa 
 srfT .Jnioq Jerfj JB UuHa srfj lo aji^q afff } ?fofiBl:n sHt -^siBiJa 
 1O3 anil arfj ot Ifijjfa aril ni nohiaoq ni bnoqeano-j II aJfifl ni 'l 
 .noijiaoq Iciulsn aii hi n WBib naad aeri B'-M! grfj -rania/jib searit ni .1 
 
 moil 
 
 aanil 
 ni 
 
 mi3J srfj ssingooST oJ isbio ni 
 srij lo 'jrigisri' srij bne .noijqhaasb 
 .nwob abiaqu amfii^sib sdi mui ot 
 
 HUJ!?. 3ril rlliw , 
 ni saaol airiJ oJ bailqqs 
 ai
 
 16 
 
 
 \V. L. H Duckworth. 
 
 >*/ E^mo Skulls, by j. Bri- 
 . r: Amur. tnst.. 1906. 
 EXPLANATION OF PLATE I. 
 
 . by Prof. A. 1 
 Section through the left Glenoid Fossa of a European. 
 
 C = Condyle of lower jaw. 
 
 E = Eminentia articularis. 
 
 F = Glaserian fissure. 
 
 G = Anterior concave portion of glenoid fossa. 
 
 P = Petrous portion of temporal bone. 
 
 S = Squamous portion of temporal bone. 
 
 The above section was cut in the sagittal plane a little to the left of the 
 deepest part of the Glaserian fissure. It will explain the diagrams drawn 
 from the sections of the casts of various Glenoid Fossae shown in figure 2, 
 as it illustrates the relations of the parts of the skull at that point. The 
 lines EGF in Plate II correspond in position in the skull to the line EGF 
 in Plate I. In these diagrams the fossa has been drawn in its natural position, 
 i.e. with the skull placed upright. In order to recognize the term 'concave' 
 as applied to this fossa in its anatomical description, and the 'height' of the 
 eminentia articularis, it is only necessary to turn the diagrams upside down. 
 
 f 111 and IV and for ma 
 - f km* illustrating Plates 1 
 - --/ ftnd kindness of Dr. Arthur 
 V.-uomy of Oxford Univ 
 
 * r ;. >.!<,. -;'. . .. ^ f /, r cranial collection of the
 
 MUSEUM BULLETIN No. 9. 
 
 PLATE I. 

 
 81 
 
 MUSEUM 
 
 ATE II. 
 
 .II 3TAJ*I TO JrffOITJOHU'txS 
 (.9SI3 IfilUJSn) 9B880*H5Ton9lO Jtel 
 
 fuohiB BiJn9nim3= 3 
 
 .380) bk>n9JO= O 
 
 .fiinBio lo 89ii9a B ni saaol bjpri9l 
 grij lo jlgl grb oJ glttil B gnslq Is*rfgB8 9rfJ ni rfg 
 XtefBmixonqqB "bab 
 
 :'7'O ^ Bill 1 ,'J"T)J 
 
 Bhnanimg bns saeol 9ri^ lo noiJ098 9rb moyf*T!5too 
 lo noJiage 9no :nwfiib 9i9w smBigBify'gvodB 9n 
 
 ,9b9 
 
 j bnno-i nin fhn-aq B i>njs . 
 arf.t tc gmbn'a'Lnt; 911 
 
 Jngnimoiq bnc rigid bne 
 
 m fcUnaninig 
 
 9 bfebis ,<Mnl83 
 ,9viiBn 
 ( 9vbfin 
 
 ,989lfiHni2 
 
 iBlO adl lo JiBq Jagqggb 
 
 bionglg grf.1 lo 9fbbim ^dl oi 
 
 .beniftJdo surft 
 
 noqu ifift 
 
 liDB9 
 
 bnirigd J3i[ moil 
 
 lo 
 
 JB-naufli bns 1 .aoV? 
 ni aiiBluobtB 
 
 bnB , ,E .aoVI 
 -onifjIaS 
 
 7 1 Figure 9 MmL 
 
 ! lo 89f(|mBX9 91B V bnB d .E 
 
 .sinBio nfiilBTtauA owJ 
 
 no!<^O moil 989lfiriniS s le eel bionsls drfj~d8<ft>irij nobo9e B ai 8 .oVI 
 glqoaq B moil jaaqxa bluow gno Jsrfw i siriT .ritqgb all 10! gldBjtiBmgi ai bns 
 jf .Jaib nshJ;9g9y 6 noqu ^Inism Jaiadua oriw 
 bioqoiiijnB 9rfj ni saaol jidJ'lo aegnwollsrfa anI'ajrBiJeuJIi 0! bns Q .aoH 
 
 .89qB
 
 18 
 
 EXPLANATION OF PLATE II. 
 Sections through left Glenoid Fossae (natural size.) 
 
 E =Eminentia articularis. 
 G = Glenoid fossa. 
 F =Glaserian fissure. 
 
 1. European, adult cT 
 
 2. European, adult c? 
 
 3. Eskimo, adult cf 
 
 4. Eskimo, adult <f 
 
 5. Eskimo, adult 9 
 
 6. Australian native, adult d" 
 
 7. Australian native, adult cT 
 
 8. Sinhalese, adult d" 
 
 9. Chimpanzee, adult 9 
 10. Gorilla, adult d" 
 
 Casts were taken of the left glenoid fossa in a series of crania. These 
 casts were then sawn through in the sagittal plane a little to the left of the 
 deepest part of the Glaserian fissure. This corresponded approximately 
 to the middle of the glenoid fossa. From the section of the fossa and eminentia 
 articularis thus obtained, the above diagrams were drawn: one section of 
 each cast was placed flat upon the paper, and a pencil run round the edge, 
 starting from just behind the Glaserian fissure and ending at the anterior 
 limit of the eminentia articularis. 
 
 Nos. 1 and 2 illustrate the deep glenoid fossa and high and prominent 
 eminentia articularis in modern civilized man. 
 
 Nos. 3, 4, and 5 illustrate the shallow fossa and flattened eminentia in 
 the Eskimo. 
 
 Nos. 6 and 7 are examples of shallow fossae in two Australian crania. 
 
 No. 8 is a section through the glenoid fossa of a Sinhalese from Ceylon 
 and is remarkable for its depth. This is what one would expect from a people 
 who subsist mainly upon a vegetarian diet. 
 
 Nos. 9 and 10 illustrate the shallowness of this fossa in the anthropoid 
 apes.
 
 19 
 
 MUSEUM BULLETIN No. 9. 
 
 6 r 
 
 & f 
 
 PLATE II. 
 
 Figure 1 
 
 Figure 2 
 Figure 3 
 Figure 4 
 Figure 5 
 Figure 6 
 Figure 7 
 Figure 8 
 Figure 9 
 
 Figure 10
 
 * 
 
 No. 9. 
 
 
 gnbfi-tfeulli ^Idlbncm orn 
 ,8utni jnibnaoae arfj to bliud ^va8^5f^ bne riibiw srf) bns ,3830oiq bionoioo 
 .93i airfj lo gwjsi igwol arlj to Isoiq^J
 
 20 
 
 EXPLANATION OF PLATE I if. 
 
 Three Eskimo mandibles illustrating the lowness and strength of the 
 coronoid process, and the width and massive build of the ascending ramus, 
 characters typical of the lower jaws of this race.
 
 21 
 
 MUSEUM BULLETIN No. 9. 
 
 PLATE III.
 
 
 MUSEUM Bin A
 
 22
 
 23 
 
 MUSEUM BULLETIN No. 9. 
 
 PLATE III. 
 
 C. 

 
 
 juprlrfo b 
 
 - ovrT 
 
 islom arfj ^o ~i 
 .jlubfi omhiaS .A 
 ,llube omrJaS .9
 
 24 
 
 EXPLANATION OF PLATE IV. 
 
 Two Eskimo palates illustrating great breadth of palate and oblique 
 wear of the molar teeth. 
 
 A. Eskimo adult, male. 
 
 B. Eskimo adult, female.
 
 25 
 
 MUSEUM BULLETIN No. 9. 
 
 PLATE IV. 
 
 A.
 
 The first number of the Museum Bulletin was entitled, Victoria Memorial 
 Museum Bulletin Number 1. 
 
 The following articles of the Anthropological Series of Museum Bulletins 
 have been issued. 
 
 Anthropological Series. 
 
 1. The archaeology of Blandford township, Oxford county, Ontario; by W. J. 
 
 Wintemberg. 
 
 2. Some aspects of puberty fasting among the Ojibwas; by Paul Radin. 
 
 3. Pre-historic and present commerce among the Arctic Coast Eskimo; by 
 
 V. Stefansson.