640 Wisconsin Academy of Sciences , Arts, and Letters. 
It will be noticed that four of the binomial curves are ab¬ 
normal ; and that the one of length of head and body is par¬ 
ticularly ill-formed. In neither of them does either of the sev¬ 
eral vertices coincide with the mean of the measurements. It is 
quite evident that a larger number of specimens should have 
been compared in order to furnish normal curves for the various 
members and determine their average lengths. A larger series 
of specimens would probably have increased not only the range 
of variation in measurements of the several members but would 
also presumably have shown greater individual variation than 
the small series shows. 
A young male, Ho. 786, is noticeable on account of the re¬ 
tarded growth of its phalanges. Its measurements are: length 
49 ; tail 16 ; head 17 ; ear 13 ; forearm 41; third metacarpal 40 ; 
first phalanx of third digit 7 ; second 12 ; third 10 ; fourth meta¬ 
carpal 34; first phalanx of fourth digit 8 ; second 9 ; fifth meta¬ 
carpal 33; first phalanx of fifth digit 9; second 7; tibia 17; 
foot 11. 
Nyctinorrms braziliensis I. Goff. 
Fifty-nine specimens taken from the following localities: 
Hos. 394 to 433 and 435 to 441 inclusive, collected in various 
parts of the state of Morelos between Sept. 29 and Oct. 31, 1890, 
by H. L. Ward and O. M. T'eran. Ho. 434 at Ixtapalapa, Fed¬ 
eral District, June 29, 1890, by H. L. Ward. Hos. 442 to 452 
inclusive, were collected March 8, 1888, at Taeubaya, Federal 
District, by A. Samaneigo. 
The specimens listed, although from several localities, were all 
taken within a radius of 75 miles and are probably quite free 
from geographical variation, in fact the greatest variations are 
sometimes found to occur between specimens from the same lo¬ 
cality. 
The proportions of body and tail lengths show a moderate 
amount of variation. The longest and shortest measurements of 
the tails of the 59 specimens are found coupled with a body 
length of medium size; 57 mm. bodies bearing tails 31 and 38 
mm. long. The extent of tail extending beyond the inter- 
femoral membrane, as would naturally be supposed, is subject 
to much variation; a tail 32 mm. long having 21 mm. free while 
