40 Skeleton of the Gorilla. 



at the same time that the last two lumbar vertebrae are 



locked in between the iliac bones. The sacrum of the 



macaque is proportionally broader and more curved than 



that of the gorilla ; although tailless the sacral canal of the 



gorilla is more closed than in man. The Pelvis of the 



gorilla at first sight approaches the human in form ; the 



ilia, or haunch hones, are expanded and hollowed out on 



their inner surfaces, as in us ; but a closer inspection proves 



this part to be structurally and functionally very difierent. 



The ilium of the gorilla has no curved crest, as in man, nor 



are its surfaces alternately concave and convex as in him ; 



the outer surface, except quite posteriorly, is one large 



convexity, and all the spines are less distinct. Of th^Puhes. — 



The pecten is very prominent, and is all that remains of the 



upper surface of the horizontal ramus; the symphysis is 



much longer. Of the Ischium. — The spines o.re absen t, or quite 



TudinientaTy , and the tuberosities everted, so that they 



project beyond the lower margins of the acetabula. The 



obturator fara'men has its diameter passing from above 



downwards and inwards, in man downwards and outwards. 



There are many other points by which the pelvis of the 



gorilla approaches, in spite of these expanded haunch 



bones, that of the macaque, and inasmuch as he approaches 



macaque he recedes from man. I will not trouble the 



meeting with the measurements I have made of this part of 



the vskeleton ; for the present, let me observe that this 



expanded portion or ilium is by far less important, 



physiologically speaking, than this lower portion, or true 



'pelvis, which constitutes the passage through which the 



little stranger is brought into the world. Its diameters 



in the human species are therefore carefully studied, both 



by the accoucheur and physiologist, and one never ceases to 



admire how exactly its shape and size are adapted to the 



foetal form. But in goiilla aud macaque, as indeed in 



quadrwpeds, the diameters of this cavity are the reverse of 



those in man, the antero-posterior of the inlet exceeding that 



of either the oblique or transverse. Moreover, there are no 



prominent ischial spines, as in man, so that the mechanism 



of parturition must be very different in man and gorilla, 



very similiar in gorilla and macaque. Time will not permit 



me to dilate as much I should wish upon this important 



part of the skeleton. Enough, however, has been said to 



show that it constitutes another great structural and 



fundamental distinction between the human species and the 



