92 BULLETIN" 144, UNITED STATES NATIONAL MUSEUM 



Arizona, a skin from Tucson, Ariz., and one each from the Huachuca 

 Mountains and the Santa Rita Mountains of the southeastern part of 

 that State. It is in eastern Arizona and western Texas that inter- 

 gradation takes place with the pale form, incautus. In this region 

 the range of variation in tint among individuals from one locality 

 is sometimes so great that it would be possible without violence to 

 assign the extremes of a series to one or other of the two forms. Thus 

 of two excellent skins from near the junction of the Pecos and Rio 

 Grande Rivers, Tex., one is as dark as the average true velifer, while 

 the other is as pale as typical incautus. Again, a series of 10 skins 

 from Roosevelt, Ariz., is about intermediate; for while the darkest 

 individuals are of nearly the same dark tone as typical velifer, the 

 majority are paler, though none is quite as pallid as incautus. 

 Since the two forms hardly differ except in tint, it is often not pos- 

 sible to assign alcoholic specimens with certainty to either, but in 

 doubtful cases we have been guided by the indications of the series 

 of skins. 



There are two alcoholic specimens in the collection of the British 

 Museum labelled " Ecuador," that were received many years ago 

 from the Fraser collection. These appear to be perfectly typical 

 My Otis "velifer^ but since there is no exact locality given and no other 

 specimens are known from any part of South America, it seems 

 likely that there has been some mistake, and that the locality " Ecua- 

 dor " was supplied by inference, since Louis Eraser's name is so com- 

 monly associated with the zoology of that Republic. 



MYOTIS VELIFER INCAUTUS (J. A. Allen) 



Vespertilio sp., J. A. Allen, Bull. Amer. Mus. Nat. Hist., vol. 8, p. 71, April 22, 

 1896. 



Vespertilio incautus J. A. Allen, Bull. Amer. Mus. Nat. Hist., vol. 8, p. 239, 

 November 21, 1896. — Miller and Rehn, Proc. Boston Soc. Nat. Hist., vol. 

 30, p. 307, December 27, 1901. 



Vlespertilio] albescens? H. Allen, in Miller, North Amer. Fauna, No. 13, p. 59, 

 October 16, 1897 (Texas specimens). 



Myotis velifer Miller, North Amer. Fauna, No. 13, p. 56, October 16, 1897 ' 

 (part). — Strecker, Check-List Mamm. Texas, The Baylor Bulletin, Baylor 

 University, "Waco, Texas, vol. 29, No. 3, p. 9. Au^ist, 1926. 



Myotis incautus Miller, Proc. Biol. Soc. Washington, vol. 15, p. 155, June 20, 

 1902. — J. A. Allen, Bull. Amer. Mus. Nat. Hist., vol. 19, p. 611, November 

 12, 1903.— Miller and Rehn, Proc. Boston Soc. Nat. Hist., vol. 31, p. 121, 

 August 27, 1903. — Trouessart, Catal. Mamra. viv. foss., suppl., p. 92, 1904. — 

 Bailey, North Amer. Fauna, No. 25, p. 209, October 24, 1905. — Elliot, Check 

 List Mamm. North Amer., Field Columb. Mus., publ. 105, zool. ser., vol. 6, 

 p. 473, 1905. — HovPELL, Proc. Biol. Soc. Washington, vol. 22, p. 46, March 10, 

 1909.— Miller, List North Amer. Land Mamm. 1911, Bull. U. S. Nat. Mus., 

 No. 79, p. 54, December 31, 1912; List North Amer. Recent Mamm. 1923, 

 Bull. U. S. Nat. Mus., No. 128, p. 67, April 29, 1924.— Steecker, Cheek-List 

 Mamm. Texas, The Baylor Bulletin, Baylor University, Waco, Texas, vol. 

 29, No. 3, p. 9, August, 1926. 



