394 NOTES ON THE CANIDJ5 OF THE WHITE KTVER OLIGOCENE. 



lus is relatively longer than in Cards or even than in Daphcenus, resembling that of such 

 viverrine genera as Paradoxurus, but is not directed so strongly toward the tibial side of 

 the foot as in Daphcenus. The head with its convex navicular facet is shaped much as 

 in Canis, except that it is more depressed in the dorso-plantar dimension. In Daphce- 

 nus there is a distinct facet for the cuboid, which meets the navicular facet nearly at 

 right angles ; in Cynodictis this cuboidal facet is very much smaller and sometimes it is 

 altogether wanting, while in Canis the astragalus and cuboid are not in contact. As in 

 Daphcenus, the external calcaneal facet is more oblique in position and more simply con- 

 cave than in Canis, but the sustentacula! - facet is different from that of both the genera 

 mentioned ; it agrees with that of Daphcenus in being shorter and wider than in the 

 modern forms, but while in the former this facet is separate from that for the navicu- 

 lar, in Cynodictis, as in Canis, it is confluent with it, but at a different point; i. e., more 

 toward the tibial side. The interarticular sulcus is somewhat deeper than in Daphcenus, 

 but shallower than in Canis. In the latter we find a third calcaneal facet which forms a 

 narrow band upon the fibulo-plantar side of the head and is connected at one end with 

 the sustentacula r facet. This accessory calcaneal facet does not occur in either of the 

 White River genera. 



The calcaneum, like the astragalus, is more viverrine than canine in general appear- 

 ance and quite closely resembles that of Paradoxurus, but the resemblance to Daplicenus 

 is even more marked. The tuber is slender, compressed and proportionately much 

 shorter than in Canis; in the latter the tuber makes up more than two-thirds of the 

 total length of the caleaneum, while in Cynodictis it is about two-fifths of this length. 

 The free end of the tuber is moderately thickened and club-shaped and is deeply grooved 

 by the sulcus for the plantaris tendon. As in Daphcenus, the dorsal and plantar borders 

 of the tuber are nearly parallel and its dorso-plantar diameter is thus almost uniform 

 throughout, not increasing toward the distal end as it does in Caul*. Near the distal end 

 of the calcaneum and on the fibular side is a very prominent process for the attachment 

 of the lateral ligaments. This process is not present in the recent Canidce, but is very 

 conspicuous in the primitive carnivores, such as Dinictis and Daphcenus, and it recurs 

 among modern plantigrade ami semiplantigrade forms, such as Procyon, Gulo, Para- 

 doxurus, etc. Usually, however, it is smaller and less prominent in the fossil than in the 

 recent genera. The facets for the astragalus are somewhat different from those of both 

 Daphcenus and Canis. In the latter the external astragalar facet is in two parts, one of 

 which presents distally and the other dorsally, the two meeting at an angle which does 

 not much exceed 90° ; in the former the whole facet forms one continuously curved con- 

 vexity, not divided by an angulation. In Cynodictis the two parts are distinguishable as 

 in Canis, but they meet at a much more open angle. The sustentaculum is of moderate 



