154- 



PELVIS. 



The ilia are narrow and cylindrical; pubes 

 long, large, oblique, with no ilio-pectineal apo- 

 physis; ischia short, with horizontal raini and 

 tuberosities passing backward to articulate 

 with the transverse processes of the upper 

 coccygeal vertebrae, another bird-like arrange- 

 ment. In L.indri the sacral pieces are four, 

 with complete ankylosis, the two or three 

 upper articulating with the ilia. Ilia expanded, 

 with extended crest and external fossa, and 

 reaching to the penultimate lumbar vertebra; ; 

 ischia very short, witli more expanded tubers ; 

 jjitbes less oblique. In L. volans, or Galeo- 

 pithccus, the sacrum has five vertebrae, the 

 first only articulating with ilia. Ilia small 

 and narrow ; ischia with large posterior angle; 

 pubic symphysis very short. In the sub- 

 genus Sterops, the slender Loris presents a 

 remarkably elongated and contracted pelvis. 

 The sacrum is long and narrow, with the two 

 upper pieces articulating with ilia. Ilia slender, 

 long and columnar, and nearly parallel with 

 spinal column ; ischia small, flattened laterally, 

 placed in a line with the ilia, and very near each 

 other, so that the cotyluid cavities are closely 

 approximated ; the lateral diameters very short, 



Fig. 93. 



and the inferior outlet a mere 

 chink. The pubes are long, 

 projecting forwards, down- 

 wards, and inwards, being in- 

 clined to each other at an 

 angle of 40, causing the 

 superior outlet to be trian- 

 gular, with the base at the 

 inter- cot y laid diameter, and the 

 apex at the symphysis pubis. 

 This pelvis is also remark- 

 able for the extreme angularity 

 of the pubic portion with the 

 iliac, the ilio-pubic angle being 

 75, or less than a right angle, 

 the only instance of the kind 

 I have met with. (See fig. 

 93. a, b, c.). 



Pelvis of the slender Loris, lateral view. 



The animals most allied to the preceding 

 order of primates in the form of the pelvis, 

 taken in conjunction with their general struc- 

 ture, are the Carnivora. In these, as in most 

 multidigital animals, the pelvis is so con- 

 tracted that the trunk resembles an in- 

 verted pyramid ; whereas in man, constructed 

 for an erect posture, the base of the pyramid 

 is in the pelvis. Climbing animals, such as 

 the Apes, Bears, and Sloths, present the 

 nearest approach to the human structure in 

 this particular. 



In estimating the sacro- and ilia-vertebral 

 angles in the succeeding orders of Mammalia, 

 it should be observed that, from the coin- 

 cidence of the lumbar curve with the great 

 dorsal curvature of the spinal column and the 

 elevation of the neck, the vertebrae cannot 

 be considered as being placed in one general 

 plane, as in man. The line of direction of the 



lumbar vertebra has, therefore, been taken 

 for the sacral and iliac angles. 



The sacrum, in the Carnivora (a, fig. 94-.), 

 is narrow, flat, and triangular, with long and 

 distinct spinous processes, and placed almost 

 in a right line with the spine. In the Bear, 

 however, from its climbing habits, the sacrum 

 is broader, larger, and more massy, and the 

 sacro-vertebral angle more marked. The 

 number of sacral vertebrae is three in the 

 great majority of the species, the two upper 

 articulating with the ilia ; but in the Hyaena 

 there are but two, in the Tiger four, in the 

 brown Bear five, and in the white Bear as 

 many as seven. The coccygeal or caudal ver- 

 tebras (b) are generally very numerous. 



The ilia are moderately long, thick, and 

 narrow in their whole extent, and are placed 

 very obliquely upon the lumbar vertebrae, 

 forming with them an angle of about 150 to 

 160 ; but in the Bear and Hyaena 140 only. 

 The external surface of the elongated iliac 

 wing is concave, and the internal flat and 

 turned inwards towards the spine ; the crest 

 (c) thick, narrow, acutely arched, and pro- 

 jecting backwards beyond the spinal column. 

 The ischia are long, strong, prismatic, some- 

 what expanded posteriorly, and considerably 

 divergent, but directed in the same antero- 

 posterior plane with the ilia, forming toge- 

 ther a very long ilio-ischion element. This 

 disappearance of the antero-posterior, ilio- 

 ischial angle, which commenced in the Apes, 

 is, in the Carnivora, arrived at its greatest 

 extent, and in the Tiger is even reversed 

 or bent downwards in the opposite direc- 

 tion about 15 (see fig. 112. 5). With the 

 great obliquity of the ilia, this affords, in the 

 quadruped position, a longer and more power- 

 ful leverage for the muscles of the hinder 

 extremities to execute their characteristic 

 bounds, and, like the reverse formation of the 

 ilio-pubic angle, it is another great distinction 

 between these and human pelves. The ischial 

 tuberosities (e) have an outward direction, as 

 well as the ischia generally, and the spine (g) is 

 a mere rudimentary ridge. The pubes are short, 

 and the symphysis (/) is long, being formed 

 generally both by the ischium and pubis. The 

 ilio-pubic angle varies from 110 in the Tiger, 

 to 120 in the Lion and Leopard, and 125 

 in the Bear and Hyaena. 



The anterior pelvic outlet is smaller than the 

 posterior, from the divergence of the ischia pos- 

 teriorly ; and the cotyloid cavities are inclined 

 outwards slightly, so as to overhang the femora 

 in the prone position. 



The centre of gravity, in these animals, 

 being placed much nearer the anterior than 

 the posterior extremities, the former bear 

 the most of the weight, while the latter act 

 more as impelling agents in the powerful 

 bounds which they execute. 



The ilia of the Bear are shorter, thicker, and 

 more massive, with more expanded wings, a 

 better-marked anterior superior spine, and a 

 more marked lumbo-iliac angle ; the ischia short 

 and widely expanded, and the pubes remark- 

 ably strong, with a very long symphysis. At 



