156 



PELVIS. 



are inclined from the perpendicular about 70 

 in the elephant, being about 5 more than in 

 the fossil Megatherium and Mylodon. The 

 pelvis of the Elephant is altogether remarkable 

 for its perpendicular position, the lumbo- 

 iliac angle being about 120 only, and the 

 pubes being advanced as far forward as the 

 iliac crest, at an angle of 100 with the ilia. 

 Thus the posterior limbs are brought more 

 under the weight of the animal. The superior 

 outlet is roundish, but broader at the pubes 

 than at the sacrum, and the antero-posterior 

 diameter is but little larger than the trans- 

 verse. In the fossil Elephant, however, the 

 antero-posterior diameter is greater in pro- 

 portion. The female Elephant has the pelvis 

 more open than the male, and the borders 

 more trenchant, according to Cuvier. Blumen- 

 bach states that the round ligament, as well 

 as the cotyloid depression, is wanting in the 

 Elephant. 



The pelvis of the fossil Mastodon is much 

 less depressed and expanded than that of the 

 Elephant, according to Cuvier, and its outlets 

 smaller, showing that its abdomen was of 

 less size. 



The Rhinoceros has four sacral vertebra?, 

 three articulating with the ilia, and supported 

 by articulation with last lumbar transverse 

 processes ; and the caudal vertebrae numerous. 



The ilia are large, massy, short, and ex- 

 panded, though much less so than in the 

 Elephant ; with the anterior iliac fossa well 

 marked, and the dorsum also generally con- 

 cave from side to side, from the backward 

 curvature of the inner border to be applied 

 to the sacrum. The crest is large, and the 

 anterior superior spine turned forwards, as 

 in the Elephant, and forked at the end. The 

 ischia are longer than in the Elephant, with 

 thick tuberosities, turned much outwards. 

 Pubes long, and united at a sharper angle, 

 with prominent ischio-pubic symphysis. The 

 lumbo-iliac angle in the two-horned: variety 

 is 125, the ilio-ischial 145, and the ilio- 

 pubic 150, making the pubis nearly at right 

 angles to the spine. The whole pelvis is 

 shallow, with the ischio-pubic portion placed 

 more backward than in the Elephant. The 

 anterior outlet is large and oval, with the 

 longer diameter antero-posterior. In the 

 fossil variety there is no fork on the anterior 

 superior iliac spine, and the obturator fora- 

 mina are more elongated. 



In the Hippopotamus thesaa'um is very broad 

 and flat from side to side, though arched con- 

 siderably longitudinally ; with a considerable 

 angle, and articulated with last lumbar trans- 

 verse processes. The iliac wings are almost 

 plane with it, forming a lumbo-iliac angle of 

 about 150, and are less expanded, smaller, 

 and more slightly convex, with the two su- 

 perior spines directed much dorsally, espe- 

 cially the posterior. The ischia are long and 

 comparatively slender, and directed dorsally, 

 forming a large angle with the ilia, and sup- 

 porting large and massy tuberosities, which 

 are parallel to each other, and project by a 

 prominent tubercle dorsally above the coccy- 



geal vertebra, a peculiarity which causes this 

 pelvis to look altogether like that of the Ox. 

 The pubes are elongated, and the ischio-pubic 

 symphysis also long. The obturator foramen 

 is large, and the plane of the acetabulum 

 looks downwards and outwards, and is placed 

 at an angle of about 50 from the perpen- 

 dicular, being 20 less than that of the Ele- 

 phant. The whole pelvis has an open, light, 

 oblique, and flat appearance, with the ischio- 

 pubic portion placed more backwards than 

 either the Elephant or Rhinoceros. 



In the Hog the sacrum is narrow, the ilia 

 and ischia more elongated, and the latter closer 

 to each other, with prominent and parallel 

 tuberosities. The whole pelvis is elongated and 

 approaches the Carnivora type, as is particu- 

 larly seen in the ilio-pubic angle (120). The 

 lumbo-iliac angle is about 145. 



In the Tapir are three sacral vertebras, the 

 two upper articulating with ilia, and forming a 

 sacrum arched considerably, both transversely 

 and longitudinally, and with an imperceptible 

 angle. The ilia are remarkable for their long and 

 somewhat rounded shafts, and the sudden ex- 

 pansion of the wings on each side, so as to form 

 a T shape, of which the branches are directed 

 obliquely antero-posteriorly, the posterior 

 branch being articulated to the sacrum, into 

 which they bite well. The crest is thus made 

 slightly concave instead of convex. The sacro- 

 iliac facet, which in most mammalia is lunated 

 in shape, with the convexity directed to the 

 acetabulum, and the concavity to the spinal 

 column, is in the Tapir of a peculiar shape, 

 narrowing suddenly between the two sacral 

 vertebra, and then again expanding, forming 

 two distinct sacral "joggles." The ischia 

 are long, with tubers projecting dorsally ; 

 pubes directed inwards. The lumbo-iliac angle 

 is comparatively very acute (125) ; the ilio- 

 pubic large ( 145) ; and the ilio-ischial well 

 pronounced (140). The whole pelvis is very 

 like that of the Horse, but is distinguished by 

 the greater breadth and curves of sacrum, and 

 by more massy proportions, and more distinct 

 T-shaped, and greater expansion of the ilia. 

 The pelvis of the fossil Paleotherium has some 

 resemblance to that of the Tapir, but the ilia 

 are longer and more prismatic, and the ischial 

 tuberosities less developed. That of the 

 Anoplotheriurn is a link between the Tapir and 

 Camel. 



The Solidungula form a connecting pelvic 

 link between the foregoing and the Rumi- 

 nants. 



The sacrum of the Horse is flat, not curved 

 longitudinally so much as in Ruminants, and 

 placed in the line of the dorsal curve. It 

 is moderately broad between the ilia, but 

 narrows suddenly posteriorly, and reaches 

 as far backwards as the middle of the 

 ischia. This is the same position as in the 

 Pachyderms proper ; but in the Ruminants, 

 whose pelves are more oblique, the sacrum 

 scarcely reaches to the symphysis pubis, as is 

 seen in the pelvis of the Ox (Jig. 97.). 

 The sacral pieces are six in number, two only 

 articulating with the ilia, and the sacral spines 



