4 EXTINCT TYPE OK DOU. 



bones known. As regards those from North America, referred to Cants and 

 allied genera, a comparison is needless, the differences are at once so obvious. 

 With the Miocene genus Amphicyon there are some points of resemblance: 

 both are stout, short-legged forms; and both lack the supracondylar foramen 

 so characteristic of the ordinary dogs. The Amphicyon vefus, described by 

 Dr. Leidy. from the bad lands of White river, Dakota, from parts of the 

 skull and fragments of jaws, was evidently an animal of about tin' same 

 size. From what is known of the cave fauna of the region in question, 

 however, it seems hardly probable that the remains here described are 

 referable to a Miocene genus. Unfortunately the skull, which would give 

 a much better clue to the affinities of the beast, is lacking, although it is 

 not improbable that it still exists, as well as many other parts of the skele- 

 ton, in the cave near the point where the bones here described were gathered. 



Pachycyox, gen. nov. 

 Scapula equal in length to the humerus. Pelvis greatly arched, equal in 

 length to the femur. Tibia a little shorter than the femur. Limb-bones 

 remarkable for their thickness in comparison with their length. 



PACHYCYON ROBIXSTUS, *p. ixir. 



Scapula (pi. 1, tigs. 1 — 4). — The scapula, in comparison with this bone 

 in the fox, coyote, wolf, and various races of the dog, presents, separately 

 considered, several points of interest: (1.) The angle near the proximal end 

 of the anterior border (see pi. I, fig. 1) is unusually strongly developed, and 

 is placed much nearer the suprascapular border than in the animals named. 

 (2. ) The portion below the origin of the spine is much elongated, so that 

 while the acromion process is well developed, it falls short of a plane par- 

 allel to the glenoid surface, instead of passing slightly beyond it, as in the 

 coyote, dog, well', etc. This portion of the scapula is actually 1""" longer 

 than in the coyote, while the whole length of the scapula is one eighth less. 

 (.'{.) Tin' posterior border is strongly everted. This is in part due to the 

 warping of the bone, as is shown by minute fractures; yet there is evidence 

 of a considerable amount of normal eversion, much more than is usual in the 

 Canidce. With these exceptions, there is nothing in this bene by which it 

 is especially distinguishable from the scapula of a dog of corresponding size, 

 excepl possibly the greater depth of the spine. Taken, however, in connec- 



