122 R. S. Lull — Netv Tertiary Artiodactyls. 



Tibia and fibula (figs. 20, 21). — The tibiae in Aletomeryx 

 and Antilocapra are quite comparable, as are the distal 

 ends of the fibulae, which are complete bones in them- 

 selves, with the merest vestige of a shaft. Proximally 

 the fibula of Antilocapra is reduced to a thoroughly anky- 

 losed bony process depending from the outer posterior 

 corner of the tibial head. In Aletomeryx, on the other 



24A 



M24-B 



Fig. 21. Left tarsus and metatarsus. A, outer aspect, Antilocapra: f, 

 distal end of fibula. B, Aletomeryx: f, distal end of fibula; v, vestige of 

 metatarsal V. One-third natural size. 



Fig. 22. A, phalanges of Aletomeryx, dorsal aspect; B, left pes of Aleto- 

 meryx, anterior aspect. One-third natural size. 



Fig. 23. A, proximal end of left cannon-bone of Aletomeryx, showing 

 vestigial metatarsal II ; B, rear aspect of same, showing metatarsals II, III 

 and IV combined, and V, the last being free. One-third natural size. 



Fig. 24. Patella. A, Antilocapra; B, Aletomeryx. One-third natural 



