a ee ee 
ApRIL, 1914. MAmMMALS OF NORTHERN PERU — Oscoop 181 
are larger and wider than in Furipterus and the principal cusps are 
higher, but the cingulum is so slightly developed as to be visible only 
upon the closest examination. The lower incisors, canine, and pre- 
molars are more similar in the two genera than the corresponding upper 
teeth, but in Amorphochilus there is practically no tendency to the 
development of cusps from the cingulum. A slight space exists between 
the inner pair of lower incisors. Lower molars with scarcely any 
cingulum. Entoconids relatively farther from metaconids; commissure 
- from entoconid to hypoconid higher and stronger, especially in the first 
lower molar, in which the entoconid is but slightly higher than the 
commissure, which forms a broad blade. 
The following measurements have been taken: Male, measured in 
flesh: Total length 86; tail 28; hind foot 7. Female, in alcohol: Total 
length 83; head and body 54; tail 29; hind foot 6.5; forearm 36; third 
digit: metacarpal 34.4, 1st phalanx 5.2, 2nd phalanx 22.2; fourth digit: 
metacarpal 31, 1st phalanx 6.8, 2nd phalanx ro.5; fifth digit: metacarpal 
31.2, 1st phalanx 10.5, 2nd phalanx 6.7; tibia 18; calcaneum 15.3. 
Skull: Greatest length 12.1; basal length 11.3; interorbital constriction 
13.1; zygomatic width 7.3; mastoid width 6.5; maxillary width at base 
of M ? 4.8; width between tips of canines 2.5; width of braincase 5.8; 
depth of braincase including audital bull 6.7; frontal angle to occiput 
7.6; upper toothrow, C to back of M ‘ 4.7; width of M * 1.3; lower tooth- 
row including incisors 5.7. 
2 Myotis nigricans (Wied). 
Six specimens, Moyobamba. 
Although fairly common and widely distributed, vespertilionine 
bats usually are more difficult to obtain in South America than those 
of other groups. In almost all cases where we saw them, it was under 
conditions where shooting was extremely difficult. While staying at 
“Los Bafios,” near Moyobamba, we discovered the roosting place of 
some of these small bats in the side of the wall of a house, the only 
entrance apparent being a crevice ina door jamb. A light net stretched 
over this crevice early in the evening soon entangled six bats, evidently 
all that were roosting in that place, for no further captures were made 
although the net was kept there for several days. Such differences as 
appear on comparison of these specimens with others from eastern 
Brazil are not sufficiently marked to warrant any separation at the 
present time. 
