deral_: Chicomostoc, Cerro Teutli,
2-2/5 mi. NNW Milpa Alta, 2620 ft., 18. _Oaxaca_: Cuicatlan, 600
ft., 1; 3 km. WNW Dominguillo, 730 ft., 2. All these specimens are
in the Museum of Natural History at the University of Kansas.
Little discernible geographic variation was found in these
specimens of _L. n. nivalis_. No specimens could, with certainty,
be classed as intergrades between _longala_ and _nivalis_, but it
is thought that intergrades will be found in western San Luis
Potosi or in Zacatecas or in both states. Dalquest (Mammals of the
Mexican State of San Luis Potosi, Louisiana State Univ. Studies,
Biol. Sci. Ser. No. 1, pp. 27-28, 1953) refers five specimens taken
from Hda. Capulin, southeastern San Luis Potosi, to _L. n.
nivalis_. Measurements by Dalquest are in accordance with other
measurements of _L. n. nivalis_ listed above.

The name _L. n. yerbabuenae_ Martinez and Villa, was based on
specimens from Yerbabuena in the state of Guerrero. The specimens,
including the holotype, on which this name was based have been
destroyed. Luis de la Torre (Fieldiana, 37:698, 1955) examined a
topotype of _yerbabuenae_ and was unable to distinguish this
specimen from a topotype of _nivalis_ from Orizaba. Davis and
Russell (Jour. Mamm., 33:236, 1952) identified as _L. n. nivalis_
one bat from Morelos, taken approximately 32 miles NE of the type
locality of _yerbabuenae_, noting that its third finger was much
shorter than in specimens from the Big Bend of Texas. I judge _L.
n. yerbabuenae_ to be a synonym of _nivalis_ as does de la Torre.

Acknowledgment is made to Dr. W. B. Davis of the Agricultural and
Mechanical College of Texas and Mr. Colin C. Sanborn of the Chicago
Natural History Museum for loan of comparative material. I am
grateful also to the Kansas University Endowment Association and
National Science Foundation for support of field work, and to Dr.
Rollin H. Baker for guidance in my study.

_Measurements._--The following measurements in millimeters include
those of the type, and the average and extreme measurements of the
type and 22 adult topotypes: total length, 79, 79 (73-86); length
of hind foot, 16, 16 (14-17); length of ear, 16, 16.5 (15-17);
length of forearm, 50.0, 50.6 (47.3-55.0); greatest length of
skull, 28.1, 27.5 (26.1-