NEW DEER FROM CENTRAL AMERICA. 377 
the contrary, the horizontal plate of the vomer extends back far 
enough to cover the suture between the presphenoid and 
basisphenoid, and the free posterior margin of the vertical 
plate is straight or only moderately emarginate. In C. cla- 
vatus the form of the vomer is that of Cariacus, and not of 
Coassus, 
As a second distinguishing character, I find that in all the 
species of the subgenus Cariacus the osseous walls of the external 
auditory meatus are incomplete in the centre behind, while in 
Coassus the vacuity occurs much higher up. In this, as in the 
last character, C. clavatus shows a relationship to species of the - 
subgenus Cariacus. 
The third character to which I shall call attention relates to 
the arrangement of the hair on the face. The matter of the 
arrangement of the hair, as Sir Richard Owen has somewhere 
stated, deserves more attention than it has thus far received. 
So far as my observations go, the style of arrangement is very 
constant in individuals of the same species, or in the species of 
a group. In all the Cats, for example, the hair on the nose, in 
advance of the eyes, has the tips directed forwards. In all 
species of Bovine which I have examined the hair immediately 
bordering the muffle or rhinarium is reflexed, but that imme- 
diately behind has the tips directed forwards. In the horse, as 
is well known, there ig invariably a leng and very definitely 
marked “ part” in the hair on the flanks, immediately in front of 
the hind leg. Examples of this kind might be greatly multiplied, 
but it may suffice in this place to say that, considering the con- 
stancy in the position and form of these “parts ” and divisions 
of the hair, there is, I believe, no reason why they may not be 
trusted as indications of relationships. 
In all the species of the subgenus Cariacus I find that the 
hair on the median line of the head is directed backward 
without interruption. In Coassus, on the contrary, there are in 
the median line two “poles,” or points from which the hair 
radiates in every direction. One “pole” is on the crown, and 
the second about midway between the eyes and the rhinarium. 
In front of the second pole the tips of the hair are directed 
forwards to the nostrils. In C. clavatus the arrangement is 
that of the subgenus Cariacus, the tips of all the hairs in the 
ZOOLOGIST.—ocT. 1889. 24 
