236 MEMOIRS OF THE UNIVERSITY OP CALIFORNIA. 



verse processes. The anterior border of the lamina in this region is usually 

 only slightly concave. The small tubercles which commonly appear immediately 

 above the rib-articulation on the transverse processes of the third to the tenth 

 dorsals are commonly rather small compared with those of many canids. On 

 the twelfth and thirteenth dorsals the metapophysial processes are not dis- 

 tinctly separated from the zygapophyses by an antero-median notch as in some 

 other canids, but the inner side of the metapophyses is nearly continuous with 

 the prezygapophysial faces. 



The lumbars are closely similar to those of the modern timber wolves. They 

 seem generally to show the same tendency of the inner side of the metapophyses 

 to grade into the inner face of the prezygapophyses shown in the most pos- 

 terior dorsals. 



The sacrum varies somewhat in form, being wider posteriorly in some indi- 

 viduals than in others, this difference being possibly due to sex. It does not, 

 however, seem to depart distinctly from the form seen in Canis lupus. The 

 posterior extensions of the transverse processes of the last vertebra included 

 in the sacrum commonly extend only a short distance behind the posterior 

 articular face of the centrum, but vary somewhat in this respect. The spines 

 of the posterior vertebrae included in the sacrum are higher than in a specimen 

 of C. occidentalis available for comparison. 



It is not easy to make certain of the form of the tail and of the number of 

 vertebrae included in it; so far as can be determined, the number of caadals 

 did not vary distinctly from that in C. occidentalis. The size of the tail as 

 indicated by the form of the posterior region of the sacrum was not very dif- 

 ferent from that of the modern timber wolves. The individual caudal centra 

 are not found to differ in form from those of the timber wolves. 



"No peculiar characters are noted in the elements of the rib-basket and 

 sternum. 



EXTREMITIES AND ARCHES 



The form and proportions of the limbs in Can is dims show that it was an 

 animal constructed on much the same lines as the timber wolves, though some- 

 what heavier, with the limbs lighter in relation to the head. It was probably 

 slower-footed than the modern forms. 



Anterior Arch and Limbs. — The scapula varies somewhat in the series of 

 specimens available, but is in general hardly to be distinguished from that of 

 Canis lupus or C. occidentalis, excepting in its larger size. The region of the 

 infraspinous fossa is commonly very wide, and the area for attachment of the 

 teres major is distinctly marked. 



The humerus is a massive bone compared with that commonly seen in the 

 Canidae. The deltoid ridge and the tuberosities are usually very strongly de- 

 veloped. The ulna and radius are both heavy elements. The ulna is not dis- 



