THE FAMILIES AND GENEKA OF BATS. 
161 
oped and nearly equal in size, the widening and shortening of the 
crown displacing the latter cusp, so that both appear to be on ante- 
rior side of tooth, the hypocone suggesting a protocone and the 
protocone an enormously enlarged protoconule. Paracone and meta- 
cone well developed, forming, with their commissure, the trenchant 
outer edge of tooth. Outer cingulum obsolete in m x , well developed 
in m 2 . Inner cingulum distinct in both and extending to tip of 
paracone. Second upper molar slightly more than half as large as 
first, its greatest length at middle instead of along outer edge, the 
cusps all much reduced, particularly the metacone and hypocone, the 
latter being shelf-like in form and sometimes practically absent. 
Third upper molar reduced to the vanishing point, absent in some 
species and present in others as a rounded flattish remnant smaller 
than metacone of m 2 , close beneath which cusp it is situated. This 
tooth is so small that its presence or absence has no effect on the form 
of the maxillary at back of tooth row. First and second lower mo- 
lars alike in general structure, but first is the larger, and its greatest 
width is at middle or posteriorly, while that of the second is in front. 
The Stenodermine type of tooth is here seen in its most perfect devel- 
opment, though Centurio presents a more extreme phase. The crush- 
ing surface is large, finely and ^closely wrinkled, and slightly en- 
croached upon by the cusps. Protoconid low, but long and well 
developed, without cutting ridge on inner side. Hypoconid. distinct 
though low in m 1 ; obsolete or flat in m 2 . Metaconid high, narrow, 
and subterete, connected with cingulum in m 2 , the cingulum passing 
its base in m t . Entoconid low but distinct, subterete. Between 
metaconid and entoconid the cingulum occasionally rises to a dis- 
tinct trenchant cusp. Third lower molar absent or present. When 
present slightly larger than m 3 and with a small antero-internal 
cusp, probably the protoconid, but area of crown not or scarcely 
greater than that of metaconid of the other molars. Skull with 
moderately wide, slightly elevated brain case, wide-spreading 
zygomata and rather short, low rostrum. Length of rostrum 
slightly more than half that of brain case and about equal to lach- 
rymal breadth; depth through lachrymal region less than half 
lachrymal breadth. Palate moderately wide, the distance between 
the second upper premolars about equal to that from incisor to hypo- 
cone of first molar. Ears separate. Noseleaf well developed. No 
external tail. Interfemoral membrane narrow. Calcar short but 
distinct. 
Species examined. — Artibeus coryi (J. A. Allen), A. glaucus 
Thomas, A. intermedins J. A. Allen, A. jamaieensis Leach, A. litu - 
ratus Lichtenstein, A. palmarum Allen and Chapman, A. parvipes 
Pehn, A. phceotis (Miller), A. planirostris Peters, A. quadrivittatus 
25733— No. 57—07 m 11 
