441 



[Cope. 



lations of the magnum does not agree with his description, as it makes 

 that bone articulate with the scaplioid. The second description is how- 

 ever correct, and the carpus is identical with that of Coryphoclon. (Fig. 4.) 

 In the American Naturalist, June, 1883,* I have shown that the carpus 

 of the Coiidylarthra is essentially like that of the Hyracoidea. (Fig. 3.) 



Cu 



-'-~^ 





J\ 



^V> 



Fig. 5. 



Fig. 4 — Manus of Coryphodon (original). The cuneiform is imperfect. 



Fig. 5.— Left posterior foot of Elephas indicus ; (from Cuvier). ca. calcaneum ; 

 a. astragalus; «. navicular; cjt. cuboid; ec. ectocuneiform ; mc. mesocunei- 

 form. 



Tarsus. — In the tarsus of the Perissodactyla and Artiodactyla it is well 

 understood that the cuboid extends inwards so as to articulate with the 

 astragalus, giving the latter a double distal facet. It is also well known 

 that the astragalus of the ProhoscidealL^i^ but a single distal articulation, that 

 with the navicular. It is, however, true that the cuboid is extended inwards, 

 but that it articulates with the distal extremity of the navicular instead of 

 that of the astragalus. It was shown by Cuvier that the astragalus of the 

 Hyracoidea articulates with the navicular only, and that the cuboid is not 

 extended inwards so as to overlap the latter. In 1873 Marshf stated that 

 the astragalus of the Amblypoda articulates with both cuboid and navicu- 

 lar. Finally I discovered in 1881 ;X that the astragalus of the Condylarthra 

 articulates with the navicular only and that the cuboid articulates with 



* Page 522. 



t American Journal Science and Art, January, 1873. 



X Ameiican Naturalist, 1881, p. 1017. 



