1886.] The Phylogeny of the Camelide. 615 
The question of the origin of the Pantolestidz is that of the 
origin of the suborder ‘Artiodactyla. This I have believed would 
be found to have been from some yet undiscovered type or sub- 
order of the order Amblypoda! None of the known families of 
that order can have occupied this position, for although their 
general organization is appropriate, their superior and inferior 
molar teeth have been modified too much from the simple tritu- 
bercular type on which they are built. The ancestor of Panto- 
lestes was an amblypod with the tubercles of its tritubercular 
Superior molars entirely simple or conical. No such form has 
yet been discovered, but I have, in anticipation of such discovery, 
named the suborder the Hyodonta. 
= f Co igi Th iform is imperfe 
> l zoryphodđon (original), e cuneïform is imp , 
Ore it i £, lunar; Cu, cuneiform; 7z, trapezium; 7v, trapezoides; My, magnum ; | 
» Sncitorm, 
Fig. 4. Fig. 5. ; : 
_ Fic. oo anterior foot of Phenacodus primevus, one-third natural ae eE 
IG, 5 i 
appear in the Morphologisches Jahrbuch, takes the position that 
the Artiodactyla have been directly derived from the Taxeopoda 
and from the family of the Periptychidæ, thus leaving the Ambly- 
Poda out of their phylogeny. In this I cannot agree with him," 
and for the following reasons: ) 
The evolution of the Diplarthrous, or alternate wrist-and-ankle- 
ned Ungulata (Fig. 6), from the Taxeopoda, or straight-rowed 
| wnst-and-ankle-boned Ungulata (Fig. 4), has been by the rotation — 
: vey Toceedings Amer. Philosoph. Society, 1882, p. 447. Report U. 5. Geol. Sur- 
2 TE, m, 1885, p. 382. 
1e logischer Anzeiger, 1886, No. 222. oe s 
. Podon, adition that the carpus of the Periptychidæ (which is unknown) is taxeo- 
» as I have supposed, 
j vou. XX.—nNo, vir, 4t 
