three specimens are known; two are from Piaxtla, Puebla, and
the third is from the Isthmus of Tehuantepec. Only the specimen from the
Isthmus has a complete skull. The broken skull of the holotype is partly
separated from the skin of the head and in such a manner as to reveal
the teeth. The skull of the holotype seems to be broader (relative to
its length) across the mastoids and posterior parts of the zygomata than
in _R. tumida_ or than in _R. parvula_. My comparisons indicate that
_Rhogeessa gracilis_ has larger (longer and wider) ears than _R.
parvula_ and _R. tumida_ and that it is specifically distinct from the
two last mentioned kinds.

The two other nominal species from Mexico, _R. parvula_ and _R. tumida_,
were named and described by Harrison Allen (Proc. Acad. Nat. Sci.
Philadelphia, 1866: 285 and 286, respectively) on the basis of three
specimens in the United States National Museum. Two were from the Tres
Marias Islands and were the basis of the name _R. parvula_; the third
was from Mirador, Veracruz, and was the basis of the name _R. tumida_.
These specimens seem to have been preserved in alcohol. I have examined
the skulls of two of these. One (U.S.N.M., new number 37329, old number
7842) is alleged to be the paratype of _R. parvula_ and the other
(U.S.N.M., 84021) is alleged to be the holotype of _R. tumida_. In the
glass vial containing skull No. 84021, there is a label in the
handwriting of Gerrit S. Miller, Jr., bearing the following information:
"In the orig. descr. the number of this sp. is said to be 8195. This is
an error. Specimen catalogued 3.1.98 G.S.M. Jr." On the back of a second
label in the skull vial there is written, "There is no doubt that this
is the type skull. It was returned by H. A. with no. given in orig.
descr. G.S.M. Jr." In the catalogue of the U. S. National Museum there
is the statement that the type of _Rhogeessa tumida_ was collected by H.
A. Grayson.

The name _Rhogeessa parvula_ was based on two specimens (Smithsonian
Institution Nos. 7841 the type and 7842, in alcohol, collected by Col.
Grayson in the Tres Marias Islands off the west coast of Mexico.) The
type seems never to have been returned from the Academy of Sciences of
Philadelphia to the U. S. National Museum in Washington, D. C., and
cannot (in 1951) be found in Philadelphia or anywhere else. The skull,
but no other part, of the second specimen is in the United States
National Museum under the catalogue number 37