the Marsh Collection, etc. 125 



Oligocexe Caxicle. 



Cy no did is Bravard and Pomel. 



With one exception, all of the American forms of this 

 genus are represented in the Yale Marsh Collection. 

 Some of these species are based on slight but usually 

 constant variations, although there may be some question 

 as to specific rank for them. 



Cynodictis angustidens (Marsh). 



Fig. 1. 



J 



Fig. 1. — Cynodictis angustidens (Marsh). Holotvpe. X 3/2. A, occlusal 

 view of premolars; B, external view of right ramus. 



In 1871, Professor Marsh described an " anterior por- 

 tion of a right lower jaw, containing the last three pre- 

 molars, and the canine" (p. 124), under the new specific 

 name Ampliicyon angustidens. This species is identical 

 with Cope's Canis gregarius, proposed in 1873, and, 

 therefore, has precedence over the latter, since both 

 belong within the genus Cynodictis. 



The evidence, on which I base these conclusions, is 

 derived from the types themselves and from the descrip- 

 tions of them. Both types are lower jaws. Marsh's C. 

 angustidens and Cope's C. gregarius are considerably 

 smaller than the red fox; in both P 1 is one-rooted, P 4 has 

 median and basal lobes, forming a cutting edge in line, 

 the ramus is slender and deep, while the "premolars are 

 low and compressed, P 2 _ 4 have anterior basal tubercles, 

 while P 3 _ 4 p 3S ss a posterior basal tubercle and cin- 

 guluni. 



Am. Joub. Sci.— Fifth Series. Vol. Ill, No. 18 —June 1922 

 30 ? 



