SCHIN. YOSCHIDA ,87 
the former than on the latter, also that the fore foot is a truer toe-walker 
with one hoof than the hind foot. 
P'inally, I have classified the Equidae according to the number and posi- 
tion of the Ergots and Callosities, which are rudimentary toes, in order to find 
out what condition the rudimented toe has on different kinds of Equidae and 
how the finger and toe have developed, as follows : 
1. With Callosity and Ergot on both fore and hind feet. 
2. With Callosity on fore foot but not on hind foot, and Ergot on hind 
and fore foot. 
3. With Callosity on fore foot but not on hind foot, and Ergot on hind 
but not on fore foot. 
4. No Callosities or Ergots on either fore or hind feet. 
To compare with the Ungulata I have given the following table : 
1 . With two after claws on both fore and hind feet, all of the same size. 
2. With two after claws on both fore and hind feet, but larger on the 
hind than on the fore feet. 
3. With no after claws. 
From the above table I can draw the following inference : from the fact 
that the fore extremities are always used for picking up food or for means of 
attack, their digits are more developed than those of the hind which are only 
used for support or to assist movement. The Callosity, which, as written 
above, is always more developed, must be the rudimented organ which was 
formerly used by Equidae for picking up food or as a weapon of attack. 
There must also be some connection between the facts that the Ergot is always 
larger on the hind foot among Equidae, and the after claw among cattle. 
In order to make this clear, if the foot bones of those animals which now 
possess five fingers are compared with those of the Equidae, the following 
conclusion may be drawn : the first finger of Equidae was the earliest rudi- 
mented, as the hind foot finger of the present dog, then the second and fifth 
fingers were rudimented, which condition may be seen in the foot of the pre- 
sent pig. Still more rudimented second and fifth fingers are to be seen in 
