916 THE WHITE RIVER FAUTSTA. 



Galecynus gregarius Cope. 



Bulletin U. S. Geol. Survey Terrs., VI, p. 181. 



Cania gregarius Cope. Paleontological Bulletin No. 1(5, p. 3, August iO, 1873. Annual Report U. S. 

 Geol. Surv. Terrs., 1873 (1874), p. 506. Bulletin U. S. Geol. Surv. Terrs., 1879, p. 58. AmpU- 

 cyon gracilis Leuly. Proceedings Academy Philada., 1856, p. 90; 1857, p. 90. Extinct Mam- 

 malia Dakota and Nebraska, 1869, p. 36; PI. I, fig. 7 ; PI. V, figs. 7-9. Not Amphici/on gracilis: 

 of Pomel. 



Plate LXVIIa, figs. 7-11; LXVIII, figs. 5-8. 



In the White River beds of Colorado this species is more abundant 

 than all the other carnivora together, and is the only one that bears due 

 proportion to the numbers of rodentia, on which it no doubt depended for 

 food. Slight and unimportant variations may be observed among the 

 numerous specimens. In the Oregon John Day it is less abundant. It is a 

 common species of the White River bad lands of Dakota and Nebraska. 

 Mandibles from Colorado present the following characters: 

 About half the size of the red fox {Vulpes fulvus), or equal to the V. 

 littoralis, Baird, but with relatively deeper mandibular ramus than either. 

 The premolars are in contact with each other, and the middle posterior lobe 

 is well developed, except in the first, wdiicli is also one-rooted. Sectorial, 

 with s'out inner tubercle as high as the anterior lobe; heel rather small. 

 First tubercular with two roots relatively smaller than in the species last 

 described, with two anterior and one posterior tubercle. The second tuber- 

 cular is very small, and has a single subcompressed or round root. It 

 remains in very few specimens, and in a few has evidently never existed 

 A premaxillary with part of the maxillary bone displays parts and alveoli 

 of two incisors, one canine, and the first premolar. There is scarcely any 

 diastema, and the canine is compressed oval in section. The exterior in- 

 cisor is quite large, exceeding by several times the inner one. The pre- 

 maxillary bone has but little anterior production. 



Measurements. 



M. 



Length of molar series 0.036 



Length of premolar series 019 



Length of fourth premolar 006 



Length of sectorial 009 



Width of sectorial 004 



Height of sectorial 006 



Depth of ramus at sectorial 010 



