468 
THE STRUCTURE AND RELATIONSHIPS OF ANCODUS. 
.„d bro»d, having an extensive sature with tho aaaal There- is no distinct pala- 
tine ntocess.and the premaxillarj spine is a slender cylindrioal lod, nhicli, on ing to 
its fragility is very generally missing from the specimens. The antermr nares are 
notably small, bnt they are less oblique in position and present more directly for- 
ward than in A. velmims. The incisive foramina are very narrow, but quite 
elongate. 
The maxillaries are of great length, the extraordinary elongation of the 
muzzle being due principally to them. The alveolar portion is low, in correspon- 
dence with the very brachyodont character of the molars, as is also the vertical plate 
which forms the side wall of the nasal chamber. This plate is, however, con- 
siderably higher than in the Ronzon species. How far the very low inaxillaries 
and, consequently, very depressed face of the latter are due to the crushed condition 
in which they are found, it is difficult to say, but the greater height of these bones 
would appear to be a constant character of the American species. The face is con- 
stricted in front of p^, and again and more decidedly in front of pi. The masse- 
teric ridge is very prominent and is continued forward to the infraorbital foramen, 
which opens above pi. Long as the maxillary is, its contact with the nasal is a 
rather limited one, the sutures with the premaxillary and frontal occupying so 
much of the length of the nasal. The upper margin of the maxillary descends 
anteriorly, its vertical height decreasing toward the front. The pahatine processes 
are long, narrow, and of nearly uniform width throughout, the inner sides of the 
two molar-premolar series forming straight and nearly parallel lines. The bony 
palate is slightly concave from side to side and almost plane from before backwuird. 
The palatal notches are deeply incised, but less so than in A. leptorhynchus. The 
maxillary is not continued so far behind the last molar as in the hitter species, nor 
is it so broadened and inflated at this point as in A. velaumis. The posterior pahv 
tine foramina occupy the same advanced and unusual jjosition as in Oreodon, 
namely, opposite ph 
The palatines are united together for a long distance, which shifts the posterior 
nares much farther back than in any of the European species, so far as the latter 
are known, though A. velaunus approximates the American type in this respect, 
^e tubular shape of the canal with its narrow opening behind recalls that of 
HycBuodon and might suggest aquatic habits, were it not for the somewhat similar 
arrangement which occurs in the deer Cariacus, wlych, of course, is altogether 
tendl l so far backward, ex- 
twl ''—r, high enough in 
into l„„ch.„.hevs, ae 
than in the European sMSsaL*°o™ “*7 considerably more so 
with a miirked deitression on the t dillerent shape. The form is oval, 
clepresmon on the ventral surface, internal to the tnedhan line. This 
