NOTES ON THE CANID.E OF THE WHITE RIVER OLIGOCENE. OOO 



liminary, it will be useful to cite Schlosser's account of the salient characteristics of the 

 hind foot among the recent Canidce. 



" Die Anordnung der Tarsalien und Metatarsalien weicht natiirlich weniger ab von 

 jener der iibrigen Carnivoren als jene der Carpalien und Metacarpalien, doeh finden wir 

 auch hier immerhin einige nicht unwesentliche Modificationen. Es hat sich das Navi- 

 culare zienilich betrachtlich verschmalert, so dass es nicht mehr die Aussenseite der 

 unteren Astragalus-Partie umhiillen kann. Das Metatarsale II, das sonst nur von zwei 

 Punkten mit dem Mt. Ill in Beriihrung kommt, legt sich hier seiner ganzen Breite nach 

 an das Oberende desselben. In Folge der Verkiirzung des Tarsus ist auch der aufstei- 

 gende Fortsatz des Mt. V sehr kurz geworden. Die Phalangen haben gleich den Meta- 

 podien nahezu quadratisehen Querschnitt, die Krallen sind sehr spitz, aber wenig gebogen, 

 haben jedoch zienilich bedeutende Lange. Die Hunde sind die ausgesprochensten Zehen- 

 ganger unter alien Carnivoren " ('88, p. 22). 



In DapJuenus the astragalus is decidedly different both from the astragalus of 

 Dinictis and from that of Cards, but approximates more the latter. The trochlea is low 

 and but moderately grooved, decidedly more than in Dinictis, but less than in the modern 

 dogs, and the articular surface does not descend so far upon the neck as in the latter. 

 The trochlea is asymmetrical, the outer condyle considerably exceeding the inner in size. 

 The neck of the astragalus is much longer than in Hoplopkoneus, Dinictis, or even than 

 in Canis, and is directed more strongly toward the tibial side of the foot ; the head is 

 depressed, but very convex. The external calcaneal facet is hardly so large or so 

 oblique in position as in Dinictis, but it is more like the facet seen in that genus than 

 like the facet of Canis. The sustentacular facet is shorter and wider than in the 

 latter, and the sulcus separating it from the external facet is very much shallower. In 

 Dinictis the sustentacular facet has a posterior concave prolongation, such as is not found 

 in Daphrenus, nor does the latter possess the distal accessory facet for the calcaneum 

 which is so distinctly shown in Canis. The navicular facet is depressed, but very convex, 

 and there is a small facet for the cuboid. 



The calcaneum is more like that of Dinictis than that of the recent dogs ; though the 

 tuber calcis is longer, thinner and more comjiressed than in either of those groups, and 

 its dorso-plantar diameter is more uniform, increasing less toward the distal end ; its free 

 end is less thickened and more deeply grooved by the sulcus for the Achilles tendon. 

 Along the outer edge of the dorsal border is a quite deep and conspicuous groove, which 

 occurs also in Dinictis, but not in Canis. The external astragalar facet is very like that 

 of the Machairodont, being more angulated and more oblique in position than in the 

 modern dogs, presenting inward as much as dorsally. The sustentaculum also resembles 

 that of Dinictis in being less oblique, much more prominent and in having its facet much 



