161 



PELVIS. 



dorsally (/). The pubcs (d) are directed 

 obliquely backwards with very short sym- 

 physis (/), and the ilio- pectineal spine (//") 

 is very large. The pelvis is altogether massy 

 and large, with long sciatic notches and con- 

 siderable obturator foramina. 



Fig. 102. 



Pelvis of the Cape Ant-eater, side view. 



In the great American Ant-eater, both the 

 ilia and ischia abut closely on the sacral trans- 

 verse processes, presenting a faint suture at the 

 line of junction. The pelvis is proportion- 

 ately smaller and lighter, and the processes and 

 spines much less marked than in the Cape Ant- 

 eater. The lumbo-iliac angle in the Ant-eaters 

 is 140, the ilio-ischial 140 ; and the ilio-pubic 

 is reversed, and about 155. 



The Manis possess pelves of the same ge- 

 neral heavy appearance as the American Ant- 

 eater. The ilia and ischia are closely approxi- 

 mated, but not ankylosed to the sacrum. The 

 symphysis pubis is short and not joined by the 

 Lschia, and the pelvic openings comparatively 

 small. 



In the foregoing Sloths and Edentata, and in 

 some of the Rodents, we have remarked the 

 tendency of the anterior symphysis to become 

 shorter and more imperfect by the absence of 

 median union of the ischia, and that this is 

 accompanied by a corresponding increase of 

 the bond of union between the sacrum and 

 ilio-ischian elements of the pelvis, by a closer 

 approximation or ossification of their uniting 

 ligaments, t.o give greater firmness to the 

 pelvis as its anterior connection fails. 



In the Insectivora and Bat tribe, this separa- 

 tion of the innominate bones is increased, and 

 the pubes also fail altogether, in many in- 

 stances, to meet in the median line. By the 

 classification of animals according to their 

 pelvci development, which is here adopted, 

 these tribes are placed much lower than their 

 general osteology allows, in the general classi- 

 fication commonly given by authors, and 

 are allied more closely to the Bird type in 

 their pelvic formation. 



Of the Tnseciivora, the Hedgehog presents 

 the least pelvic departure from the common 

 mammalian type. The sacrum is narrow and 

 triangular, and composed of four vertebrae, three 

 of which articulate with the ilia. The ilia are 

 thin and elongated, and placed on the spine 

 at an angle of 130. The ischia are slender, 

 projecting above the level of the sacrum, but 

 not touching it ; and the rami are long and 

 slender, and enclose with the pubes large 

 obturator foramina. The pubes are long, 

 slender, and obliquely directed, making an 



ilio-pubic angle of about 150. The symphysis 

 is very short, and the pelvic outlets large, with 

 the long diameters antero-posterior. 



In the Tupaia, one sacral vertebra only, out 

 of three, unites with the ilia, and there is a good 

 sized symphysis pubis, as is also seen in the 

 Tenrecs. In the genus Desman two sacral ver- 

 tebras articulate with the ilia and one with the 

 iscltia; and i\ie pubcs are very obliquely placed 

 on the ilia, and, according to Blainville, are 

 placed, anteriorly, rather in contiguity than 

 in symphysis, giving to the pelvis very much 

 of the appearance of that of the Ostrich. In 

 the MacrosceMcs there is a short and rudi- 

 mentary pubic symphysis. 



The Mole (Ta/pa) and the Shrews (Sorex) 

 are remarkable for a very narrow sacrum, com- 

 posed, according to Blainville, of four ver- 

 tebrae, but, according to Cuvier, of seven in 

 the Mole and three in the Shrews. In the 

 Mole the ilia are solidly ankylosed to nearly 

 the whole length of the sacrum. In the Shrews 

 the two first only of the sacral pieces are 

 united with the ilia. The spines in both are 

 coalesced into a prominent sacral crest. 

 Caudal pieces numerous. 



The ilia arc cylindrical, much approximated, 

 and parallel to the spinal column. The ischia 

 are much elongated, and elevated posteriorly 

 above the sacral vertebra. The pubes are very 

 short and slender, and though they unite with 

 the short ischial rami to enclose a small obtu- 

 rator foramen, do not meet in a symphysis, but 

 present an anterior interval, said to be wider 

 in the female than the male, and causing the 

 whole pelvis to assume very much a bird-like 

 appearance. The pelvic cavity and outlets are 

 so strait that the sexual and urinary organs 

 and rectum pass altogether in front of it. 



In the Bats (Cheiroptera) the sacrum (fg. 

 103, e), is very narrow, compressed posteriorly 

 into a straight continuous bone, with no lateral 

 foramina, and composed of three to four ver- 

 tebrae, which are joined by ankylosis to three 

 or four upper coccygeal vertebrae, or to more 

 in the tailed species. There are six to twelve 

 caudal bones, sometimes absent, as in Ptcropus 

 and Vampire. 



Fig. 103. 



Pelvis of the Tcrnate Bat (natural size*), anterior 

 view ; showing the inter-pubic separation (d, d'). 



The ilia (,) are narrow and subcylindrical, 

 with a thick anterior spine, placed parallel 

 to the vertebral column, and ankylosed to the 

 anterior sacral vertebrae. The ischia (<:) 

 are in the same right line with the ilia, and are 



