CARNIVORA. 



385 



vertebra much resembles that of the Felidse, while the axis bears the 

 usual large neural spine. There seem to have been 13 thoracic or dorsal 

 vertebra), ami there are clearly 6 lumbars. The anterior dorsals are 

 relatively small and opisthocoelous ; while the neural arches of the lumbar 

 vertebras bear not only zygapophyses but also anapophyses and rneta- 

 pophyses. The sacrum comprises three vertebrae, of which two unite with 

 the ilium. The long tail consists of 28 vertebrae, many bearing chevron 

 bones. The fore limb more nearly resembles that of the seals than that 

 of the terrestrial Carnivora, and the scapula, humerus, and ulna are nearly 

 equal in length. The humerus bears an enormous deltoid crest, and there 

 is a large entepicoudylar foramen. The pentadactyl manus (fig. 215 A) is 

 spreading, and the cleft ungual phalanges bear a large subungual process 

 pierced transversely by a foramen (suggestive of the correspondingly 

 developed process in -the sea-lions). In the pelvis the ilium is a strong 

 trihedral bar of bone, and the acetabuluni is shallow, with a broad 



leptorhynchua ; left mandibular ramus wanting hinder end, outer 

 aspect, nine-tenths nat. size. U. Eocene (Phosphorites) ; Mouillac, France. 

 la-3a, molars ; c, canine ; lp-4p, premolars. (After Gaudry.) 



cotyloid notch. The femur is longer and stouter than the tibia, with a 

 small third trochanter. The cnemial crest of the tibia is distinct; and the 

 fibula is comparatively stout and separate. The pes (fig. 215 B) is about 

 as large as the manus, and closely similar to the latter in all respects. 

 The large head of the astragalus is fixed much more obliquely upon the 

 neck of the bone than in any terrestrial Carnivora. The largest and best- 

 known sjxjcies is Patriofdis ferox, with the skull about as large as that of 

 a lion, from the Middle Eocene (Bridger Formation) of Wyoming. It 

 seems to have been an animal of aquatic habits, and may perhaps have 

 fed upon the freshwater tortoises which were very abundant in the Bridger 

 Lake. Numerous coprolites containing fragments of chelonian bone occur 

 in the same strata as its remains. 



Hyaenodon (figs. 216, 217). The skeleton of this highly-specialized 

 genus is almost completely known, the restoration given in the accompany - 



w. 25 



