trellus subflavus subflavus_
(specimens from Marshall Hall in Maryland, Raleigh in North
Carolina, and Barber County in Kansas) _P. s. clarus_ is paler,
of approximately equal size, and has the zygomata slightly more
expanded laterally. From _Pipistrellus subflavus veracrucis_
(Ward), specimens from 4 km. E Las Vigas, el. 8500 ft., Veracruz,
_P. s. clarus_ differs in being larger, paler, and in having a
larger skull.

_Remarks._--_Pipistrellus subflavus clarus_ is the palest subspecies of
the eastern pipistrelle. Of the specimens assigned to _clarus_ (all
taken in May and June), only two are sufficiently dark to compare
favorably with examples of typical _subflavus_. A specimen (KU 60296)
assigned to _P. s. subflavus_ from Rancho Pano Ayuctle, el. 300 ft., 6
mi. N Gomez Farias, Tamaulipas, is much darker than _clarus_. A specimen
recorded from Devils River, Texas, by V. Bailey (N. Amer. Fauna, 25:211,
October 24, 1905) has not been examined by me but presumably is _P. s.
clarus_.

_Pipistrellus subflavus clarus_ was taken along the Rio San Diego and
the Rio Sabinas, both tributaries of the Rio Grande, where park-like
stands of pecan, cypress, willow and other trees bordered these streams.
The species was not found at stock ponds or along stream courses in
adjacent places where such trees were absent. Funds for financing field
work were made available by the Kansas University Endowment Association
and the National Science Foundation.

_Measurements._--Measurements of the holotype and average and
extreme measurements of 5 adult females from the type locality,
including the holotype, are, respectively, as follows: Total
length, 85, 88.0 (85-92); length of tail vertebrae, 43, 40.8
(36-45); length of hind foot, 9, 9.4 (8.5-11); height of ear from
notch, 12, 12.6 (12-13); length of forearm, 33.8, 33.4 (32.9-33.8);
length of tibia, 14.8, 14.6 (14.5-14.8); greatest length of
skull, 13.3, 13.1 (12.7-13.3); condylobasal length, 12.6, 12.4
(12.1-12.6); breadth of braincase, 7.0, 6.8 (6.7-7.0); zygomatic
breadth, 8.1, 8.0 (7.8-8.2); mastoid breadth, 7.1, 6.9 (6.5-7.1);
length maxillary tooth-row, 4.5, 4.5 (4.4-4.6).

_Specimens examined._--Those from Texas are in the collection of
the United States National Museum, and those from Coahuila are in
University of Kansas Museum of Natural History. Total, 21. TEXAS:
Comstock