ALLEN: BATS OF THE GENUS CORYNORHINUS. 343 



total length 16 mm.; basal length 13; palatal length 7.3; zygomatic 

 breadth 8.5; interorbital constriction 4; mastoid breadth 9; width 

 of braincase 8 ; upper tooth-row 6; lower tooth-row 6.5. 



Remarks. — The subspecies pallescens is characteristic of the arid 

 and desert country of western United States as far north at least as 

 southern South Dakota. Its pallid buffy coloration recalls that of 

 other mammals that dwell in a dry open country. Its intergradation 

 with true inegalotis to the eastward seems to be very gradual, but in 

 the northwest as it enters the humid coastal area from western and 

 northern California, to southern British Columbia it merges rather 

 abruptly into the darker townsendii. In the southwest, it appears to 

 range as far east as the Pecos River in Texas and probably intergradas 

 in northern Chihuahua with the darker race of the Mexican plateau. 

 All the specimens that I have seen from Arizona and southern Cali- 

 fornia, however, seem referable to pallescens. 



The line of intergradation with townsendii seems to follow the Sacra- 

 mento Valley of California back of the coast range from a short 

 distance to the south of San Francisco about as far north as Placer 

 County, where the change comes rather abruptly. The name inter- 

 medius H. W. Grinnell was based on specimens from iVuburn, in this 

 County, but to my mind there is hardly room for the recognition of an 

 additional race. The type is well within the range of variation of 

 townsendii, while other specimens from the same locality are quite as 

 pale as some specimens of pallescens. Further records for central and 

 eastern California and for the states to the eastward are to be desired. 

 Specimens examined. — Fifty -seven, from the following localities : 

 Arizona: Fort Verde, 1 (Amer. Mus. Nat. Hist.). 

 Graham Mts., 1 (Biol. Surv.). 

 Pinal Co., 1 (Amer. Mus. Nat. Hist.). 

 Fresco tt, 1 (Amer. Mus. Nat. Hist.). 

 California: Auburn, Placer Co., 2 not typical (Univ. of Calif.). 

 Julian, San Diego Co., 1 (Univ. of Calif.). 

 Kenworthy, San Diego Co., 12 (Univ. of Calif.). 

 Lone Pine, Inyo Co., 4 (M. C. Z.). 

 Los Angeles, 1 (Pub. Mus. Milwaukee). 

 Oro Grande, San Bernardino Co., 2 (Biol. Surv.). 

 Riverside Mt., Colorado River, 2 (Univ. of Calif.). 

 Vallecito, San Diego Co., 2 (Univ. of Calif.). 

 Whitewater, Riverside Co., 1 (Univ. of Calif.). 

 Colorado: Boulder Co., 2, not typical (Univ. of Colo.). 

 Wyoming: Mammoth Hot Springs, 4 (Biol. Surv.). 



