VARIETIES OF MANKIND. 



1297 



breadth of the hips ; whilst it causes the 

 lower extremities of the femora to be some- 

 what obliquely directed towards each other, 

 so that the knees are brought more nearly 

 into the line of the axis of the body. This 

 arrangement is of the greatest importance in 

 facilitating the purely biped progression of 

 Man, in which the entire weight of the body 

 must be alternately supported upon each 

 limb; for if the knees had been kept further 

 apart, the whole body must have been swung 

 from side to side at each step, so as to bring 

 the centre of gravity over each tibia, as is 

 seen, to a certain extent, in the female sex, 

 whose walk, owing to the greater breadth of 

 the pelvis, and the separation between the 

 knees, is less steady than that of the male. 

 There is a very marked contrast between the 

 knee-joint of Man, and that of even the high- 

 est Apes. In the former the opposed extre- 

 mities of the femur and tibia are so expanded 

 as to present a very broad articulating sur- 

 face ; and the internal condyle of the femur 

 being the longer of the two, they arein the same 

 horizontal plane in the usual oblique position 

 of that bone; so that by this arrangement 

 the whole weight of the body, in its erect 

 posture, falls vertically on the head of the 

 tibia, when the joint is in the firmest posi- 

 tion in which it can be placed. The knee- 

 joint of the Orang, on the other hand, is 

 comparatively deficient in extent of articu- 

 lating surface ; and its whole conformation 

 indicates that it is not intended to serve as 

 more than a partial support. The human 

 foot is, in proportion to the size of the whole 

 body, larger, broader, and stronger than that 

 of any other existing mammal, save the kan- 

 garoo. Its plane is directed at right angles 

 to that of the leg ; and its sole is concave, 

 so that the whole weight of the body falls on 

 the summit of an arch, of which the os calcis 

 and the mctatarsal bones form the two points 

 of support. This arched form of the foot, and 

 the habitual contact of the os calcis with the 

 ground, are peculiar to Man alone. All the 

 apes have the os calcis small, straight, and 

 more or less raised from the ground, which 

 they touch, when standing erect, with the 

 outer side of the foot only ; whilst in animals 

 more remote from man, the os calcis is 

 brought still more into the line of the tibia ; 

 and the foot being more elongated and nar- 

 rowed, only the extremities of the toes come 

 in contact with the ground. Hence Man is 

 the only species of mammal which can stand 

 on one leg. The points in which the feet of 

 the anthropoid apes differ from his, all assi- 

 milate them to the manual type of conforma- 

 tion, and enable them to serve as more efficient 

 prehensile organs, whilst they diminish their 

 capacity to sustain the weight of the body 

 when it simply rests upon them. 



There is a considerable difference in the 

 form of the trunk, between Man and most 

 other mammalia ; for his thorax is expanded 

 laterally, and flattened in front, so as to pre- 

 vent the centre of gravity from being carried 

 too far forwards. His sternum is short and 



VOL. IV. 



broad compared with that of quadrupeds 



generally; and there is consequently a con- 

 siderable space between its lower extremity 

 and the symphysis piibis, occupied solely by 

 muscular parts, which would be quite inade- 

 quate to sustain the weight of the viscera, if 

 the habitual position of the trunk hail been 

 horizontal. In these particulars, however, 

 the most anthropoid Apes agree with Man. 



Returning now to the skull for a more 

 minute examination, and referring to the ar- 

 ticle QUADRUMANA for an account of the 

 principal differences presented between the 

 skulls of the ordinary Chimpanzee and Orang, 

 and that of Man, we shall take as our standard 

 of comparison the recently-discovered species 

 of Chimpanzee, designated as the Troglodytes 

 goril/a, whose cranium is considered by Prof. 

 Owen to approach in some respects more 

 nearly to that of man, than do either of the 

 preceding. This species differs from the T. 

 niger (Simla troglodytes, Vrolik) by its con- 

 siderably greater dimensions, by the greater 

 prominence of the supra-orbital ridges, the 

 enormous development of the crest, which oc- 

 cupies the place of the sagittal suture, the 

 greater strength of the zygomatic arches, 

 and the greater size of the temporal fossa. 

 For the more minute, but definite cha- 

 racters, on which the specific distinction is 

 grounded, the description by Prof. Owen 

 must be consulted.* The slightest glance at 

 figs. 800, 801, 802. is sufficient to show 

 how strongly marked are the features by which 

 the skull of this Chimpanzee differs from that 

 of even the most degraded of the Human 

 family ; but it will be advantageous to sub- 

 join Prof. Owen's enumeration of the chief 

 differences which are revealed by a careful 

 anatomical survey. These are : 



" 1. The smaller proportional size of the 

 cranium. 



" 2. The more backward position of the 

 foramen magnum, and its more oblique plane 

 in relation to that of the base of the skull. 



" 3. The smaller relative size, and more 

 backward position, of the occipital condyles. 



" 4. The longer basi-occipital, and broader, 

 flatter, and lower supra-occipital. 



" 5. The longer basisphenoid, and shorter 

 alisphenoids. 



" 6. The smaller size of the coalesced pa- 

 rietals, and their separation from the alisphe- 

 noids. 



" 7. The conversion of a greater part of 

 the outer surface of the parietals into con- 

 cavities or depressions for the lodgment ot 

 the temporal muscles, by reason of the bony 

 crest developed from the line of the obliterated 

 sagittal suture, and of the lambdoidal crest. 



" 8. The larger proportion of this crest 

 and of the squamosal plate developed from 

 the mastoid, and the smaller size of the proper 

 mastoid processes. 



" 9. The smaller size of the vaginal and 

 styliform processes, and the absence of the 



* Transactions of the Zoological Society, vol. iii. 

 p. 392. et seq. 



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