198 Fretp Museum or Naturat History — Zoéroey, Vor. X. 
paler than in E. hilarii; hairs of back, head, and sides of neck broadly 
tipped with Mars brown effecting uniform coloration of the upper parts 
and entirely concealing the deep blackish brown basal color; under parts 
mostly pale wood brown or Isabella color with the dark brown basal 
color slightly exposed in a prepared skin; hairs of the inguinal region 
bordering the interfemoral membrane soiled creamy without dark bases. 
Ears slightly thinner than in other species of Eptesicus; tragus 
relatively slender, somewhat attenuated, and less blunt at the tip than 
in E. hilarit; terminal tail vertebre excerted as in hzlarit. 
Skull small and light, decidedly smaller throughout than in E. 
hilarii; braincase much less elevated posteriorly, its depth in front only 
slightly less than behind; facial portion of skull relatively long; teeth as 
in E. hilarit, but smaller. 
Measurements:— Type, measured by collector: Total length 88; 
tail vertebrae 37; hind foot 10; forearm (from dry specimen) 35.7; pollex, 
with claw 4.7; third metacarpal 33; fourth metacarpal 33; fifth meta- 
carpal 31.9; tibia 14.3; calcaneum 13.6; tragus, from anterior base 4.5. 
Skull of type: Greatest length 14.3 (15.5);* basal length 13.9 (15) 
interorbital constriction 3.3 (3.8); zygomatic breadth 9.4 (10.1); breadth 
of braincase 6.6 (7.2); palate length, including spine 5.7 (6.5); breadth 
between tips of canines 3.1 (3.6); depth of braincase (inion to basioc- 
cipital) 5.2 (5.8); upper toothrow, including canine 5.1 (5.7); breadth of 
third upper molar 1.8 (2); lower toothrow, including canine 5.6 (6.). 
Remarks:— Bats from various parts of South America usually as- 
signed to Eptesicus hilarti, and perhaps representing a number of 
recognizable subspecies, vary somewhat in size, but so far as known all 
have decidedly larger, heavier skulls and teeth than the one above 
described. Although this species has the forearm only slightly shorter 
than in some specimens referable to hilarit, its skull is so markedly differ- 
ent that it does not seem probable that it will prove to be a geographic 
form of hilarit but rather a wholly distinct species which may be found 
at localities inhabited also by typical hilarii. Two specimens from 
Lagoa Santa, Minas Geraes, Brazil, have been used to represent E. 
hilarii. Another from Itacoatiara near Manaos on the Amazon evi- 
dently belongs to the same form. LE. dorianus, E. arge, E. andinus, 
E. magellanicus, and E. montanus all appear to be forms equalling or 
exceeding E, hilarii in size. 
* Measurements in parentheses are those of a specimen (No. 20742) of E. hilarit 
from Lagoa Santa, Brazil. 
