574 ANA.TOJMY OF VEETEBRATES. 



the terminal portions of the ungual phalanges are longer, broader, 

 and flatter than in the Gorilla, considerably so in relation to the 

 size of the whole hand,' having reference to sustaining the deve- 

 loped surface for a refined sense of touch. 



The ilium, fig. 367, A, 62, ischium, ib. 64, and pubis, ib. 63, 

 coalescing, the two latter at the sixth year, and both with the 

 ilium at about the twenty-fifth year, have been described, accord- 

 ing to the usage of anthropotomy in such instances, as a single 

 bone, under the designation of ' os innominatum.' The Human 

 characteristics are strongly marked in this part of the skeleton.^ 

 The ilium is broader than it is long, and is more concave ante- 

 riorly, fig. 398, 4, than in the Gorilla ; it is also more concave 

 posteriorly, fig. 397, especially in the vertical direction, in which 

 it is slightly convex in the Chimpanzee. The sacro-iliac symphysis, 

 fig. 398,2, 3, n, />, is subquadrate, instead of being long and narrow 

 as in the Chimpanzee. The ' crest,' a, Z», c, is much thicker and 

 much more curved ; and both angles or ' spines,' but especially 

 the posterior one, b, are more produced. These modifications, 

 and especially the developement of the ' external labrum,' fig. 

 397, c, relate chiefly to the needful increased surface of attachment 

 for the large muscles which sustain the trunk upright u])on the 

 hinder, now become the lower, limbs. The anterior border of the 

 innominatum, figs. 397, 398, «, e,^, especially that part formed by 

 the ilium, a, u, r/, is much shorter and thicker, and the ' anterior 

 inferior spine,' J, is better developed. The acetabulum, fig. 397, 

 4, is turned more toward the back of the os innominatum. The 

 great ischiatic notch, m, is shorter, but much deeper ; the spine of 

 the ischium, Z, is more produced ; the lesser ischiatic notch, k, is 

 deeper, more concave, but of the same length. The tuberosity of 

 the ischium, i, is convex, and is continued upon the outer part of 

 the bone to near the acetabulum ; in the Gorilla and Chimpanzee 

 it is more flattened, is carried further down from the acetabulum, 

 and its outer margin is produced or everted. The pubis, q, s, is 

 shorter and much thicker than in the Chimpanzee. The symphysial 

 boundary of the obturator foramen, o, is much narrower and less 

 curved. The oblique groove, t, beneath the pubic boundary of 

 the foramen in Man is not present in either the Chimpanzee or 

 Orang-utan. The cotyloid notch, 5, is broader, and the .sym- 

 physis pubis, fig. 398, ^, is much shorter than in the Anthropoid 

 apes. 



The backward developement of the ilium, b, n, for the ecto- 

 glutaeus, and the ant. inf.-spine, d, for the rectus femoris, relate to 

 » ciir. vol. V. pi. 10. 2 II, vqI y pi^ Q 



