442 Prof. W. B. Scott — Restoration of HycBnodon. 



belong the skull, neck ; nine thoracic, four lumbar, two sacral, and 

 two caudal vertebrae ; the scapula, ulna, radius, and part of the 

 carpus ; the femur, tibia, fibula, and part of the pes. The missing 

 vertebrae were restored from a second specimen which had the skull, 

 all the presacral vertebrge, tibia, fibula, and hind foot. This is 

 a young animal, still retaining the milk dentition, and is very pro- 

 bably referable to the same species [H. cruentus, Leidy) as the first. 

 Another adult specimen of the same species, slightly larger than the 

 first, consists of the mandible, axis, humerus, ulna, pelvis, and femur, 

 and allows the proper proportions to be accurately observed. 

 Other more or less fragmentary skeletons, representing various 

 species, lead to similar results, though it yet remains to be de- 

 termined how far the European species, which exhibit certain con- 

 stant differences from the American, were characterized by the same 

 remarkable appearance. 



As compared with any of the recent Carnivora, the head of 

 EycBnodon seems large out of all proportion to the body and limbs, 

 the neck short, the back, especially the lumbar region, quite long, 

 the tail short, the limbs short and slender, and the feet weak. 



The characteristic and peculiar physiognomy of the head is already 

 familiar and needs no further description. The neck seems very 

 short and slender to carry the weight of the large head, its length 

 being hardly more than two-thirds that of the skull. The axis is 

 the only cervical vertebra which is strongly developed, possessing 

 a large spine; the others are weak. 



The thorax is small, when compared with the skull, but measured 

 by any other standard is quite large and capacious. The vertebral 

 spines are developed much as in the Carnivora, and the transverse 

 processes and rib-tubercles are very conspicuous. The lumbar 

 region is quite long and powerful, the vertebra having massive 

 centra, long and heavy spines, transverse processes, etc. These 

 features are most marked in H. horridus ; the smaller species have 

 much less massive loins and evidently feebler muscles. The whole 

 back, from the neck to the sacrum, is strongly axled upward, and its 

 parts are articulated together with unusual flexibility and strength. 

 The tail is rather short and slender, and has about the same relative 

 length as in the raccoons. 



The scapula is small and, though with many peculiarities (espe- 

 cially the shape of the acromion), has a shape not unlike that found 

 in the dogs. The humerus is short and slender, and the fore-arm 

 bones still more so, though the ulna is relatively little reduced and 

 has, as in nearly all creodonts, a very prominent olecranon. The 

 manus is small, short, and broad, with five spreading digits and short 

 phalanges, terminated by heavy claws. 



The pelvis is decidedly large, even when compared with the 

 overgrown skull, and has an expanded, flattened ilium, more car- 

 nivorous than creodont in appearance. The femur considerably 

 exceeds the humerus in length, but is light and slender and has 

 nearly lost the third trochanter. The tibia is short, though much 

 longer than the radius, and the fibula is stout, with expanded ends. 



