Vol. IX] TAYLOR— COOPER'S MAMMALS 105 



tailed Mouse [printed slip bearing this name is pasted on over 

 Cooper's initials]"; reverse, eleven measurements. No. 5825: 

 original label missing; from label attached we learn that the 

 specimen is from Fort Mojave ; that it was taken in February ; 

 and that it is a male. No. 5826 : original label missing ; data 

 identical with that of No. 5825, except that the specimen was 

 taken in March instead of February. 



Skulls inside the skins ; fore feet folded posteriorly on breast ; 

 hind feet variously placed, one pair forward on the belly, the 

 others posteriorly just back of the body; the tails unskinned, 

 extended irregularly posteriorly; abdominal slits rather care- 

 lessly sewed up. 



In color characters the specimens agree closely with the large 

 series of Perognathus peniciUatns taken on both sides of the 

 Colorado River by the members of the Colorado River Expedi- 

 tion of the Museum of Vertebrate Zoology in 1910. 



Perodipus agilis simulans Merriam 



"Dipodomys agilis" (part), Cooper, Zoology, in Cronise, 

 The Natural Wealth of California, 1868, p. 445 (Notes on 

 habits) ; Amer. Nat., 3, 1869, p. 183 (Southern part of Cali- 

 fornia). 



Specimens examined.— Two : No. 5847, Univ. Calif. Mus. 

 Vert. Zool.; No. 7181, U. S. Nat. Mus. No. 5847: original 

 label missing; label attached reads "Dipodomys agilis 5 San 

 Diego Calif. Dec." No. 7181 : original label missing; old mu- 

 seum label attached reads "Smithsonian Institution Washing- 

 ton, D. C, Geol. Surv. Cal. 7181 Dipodomys [crossed out] 

 Perodipus agilis? [pencilled in later] California Dr. J. G. 

 Cooper." 



No. 5847 in rather poor condition ; skull inside skin ; fore feet 

 folded back on breast ; abdominal slits not sewed up ; bones left 

 in tail, which is turned forward beneath body, broken and some- 

 what loose at base. Specimen No. 7181 is also in poor condi- 

 tion, apparently at one time preserved in alcohol ; skull inside 

 skin [until removed for examination], forelegs disposed irregu- 

 larly forward; hind feet pointing backward; body unevenly 

 stuffed With cotton; abdominal slit not sewed up; tail broken 

 off and lost. 



