. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 162 PELVIS. still further in the Insec&vora and Cheiroptera, The increasing obliquity of the pubes also indicates an approach to the Bird type. The climbing habits of the Sloths produce a habitual vertical position of the trunk, re- quiring for the support of the abdominal viscera large open pelves. In the Ai (Bradypus tridactylus) the pelvis (fig. 100.) is remarkably slender, expanded, shallow and horizontal in direction, the pelvic openings being very large and round, and the antero-posterior diameters little large
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 162 PELVIS. still further in the Insec&vora and Cheiroptera, The increasing obliquity of the pubes also indicates an approach to the Bird type. The climbing habits of the Sloths produce a habitual vertical position of the trunk, re- quiring for the support of the abdominal viscera large open pelves. In the Ai (Bradypus tridactylus) the pelvis (fig. 100.) is remarkably slender, expanded, shallow and horizontal in direction, the pelvic openings being very large and round, and the antero-posterior diameters little larger than the transverse. The ankylosis of the innominate bones to the sacrum in these animals gives a great firmness to the support of the otherwise feeble hinder extremities, and with the great distance of separation of the acetabula, which are small and shallow, assists to a considerable degree their climbing and holding powers, and to produce that slowness and awkwardness of motion which has given them the name of Tardigrades. Fig. Pelvis of the Ai, anterior vitw. The sacrum is large, both in length and breadth, very flat, with large, open foramina, and presenting a flattened surface in place of the posterior spines and tuberosities. It is composed of five vertebras, of which the three upper (e) as well as the last lumbar (g) are ankylosed to the ilia (£). The union of the last lumbar seems to result from an extension of ossification in the ilio-lumbar ligament (?), and contributes much to increase the steadiness of the spinal column on the pelvis. The coccyx is triangular, little curved, broad and short, and is composed of six pieces. In some species it is prolonged into a tail. The ilia are short and slender, with much- expanded wings, having an anterior concavity and a plane surface posteriorly. They are ossified to the sacrum at an early period. The isckia are short and slender, and united to the last sacral vertebra, and more slightly to the two above it, by ossif
Size: 1656px × 1509px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bo, booksubjectanatomy, booksubjectphysiology, booksubjectzoology
