256 PROCEEDINGS OF THE ACADEMY OF [1894, 



('oiinty, Florida, whose characters so nearly duplicate those of the 

 Alabama specimen, I am inclined, in spite of its different faunal 

 position, to consider it the same. The colors ^iven for ine(/acrphalus 

 may l)e relied upon, though taken from a spirit specimen after dry- 

 ing. The good condition of the alcohol and the whiteness of the 

 belly hairs show them not to have been affected in the least by their 

 recent immersion. In the two half-grown young, accompanying the 

 type, the same increased relative size of the cranium, compared with 

 americanus of same age, is noticeable. 



2. Sitomys insolatus sp. uov. Type, No. .3,495, ad. ^,('oll. Acart. Nat. Sci.. 

 Phila. Oro Grande, Mohave Desert, Keru Co., California, Nov. 9th. 1893. 

 Col. by R. B. Herron. 



Description. — Size smallest of the genus west of the Mississippi 

 River, with exception of S. taylorl. Tail and feet very short, the 

 former shorter than the body minus the head, much attenuated along 

 distal half, the dark upper stripe very narrow and not reaching tip. 

 Pelage very soft, long, and dense. Upper half of head and body of a 

 uniform grayish- ochre or fawn color, not darker dorsally nor more 

 ochraceous on sides. Uuder parts }Hii-e white, the hairs of chops 

 white to their base, those of remaining under parts i)lumbeous 

 basal ly. A lanuginous tuft at superior base of ear colored like the 

 head, remainder of outer ear dusky gray, the hairs longest on anterior 

 border, very short and sparse posteriorly. Narrow, upper tail-stripe 

 dusky, like ears its color at base in decided contrast with the fawn of 

 rump. Hind feet and ankles white, the soles fully haired to proxi- 

 mal tubercle. Forelegs and feet white. Whiskers reaching tip of 

 recumbent ears. Skull smaller than in ainericanus, more nearly ap- 

 proaching ereiiilcits, but relatively wider. Nasals wide, anterior to, 

 and bluntly wedged between, the nasal premaxillary processes, as in 

 eremicus. 



The width of the mandible of Insolatus equals nearly half its 

 length, and the coronoid process is relatively nearly as large and 

 hooked as in Oin/cho)nys nonoiia, in the first character resembling 

 eremicus, and in both departing radically from aiiin-lnoiux. The an- 

 terior loop of the first upper molar is a strongly indented trefoil, the 

 inner foil being twice as large as the middle one, which, in turn, is 

 twice as large as the outer foil. 



Measuremetits. — Total length, 15<'S ram; tail vertebrie, 76; hind 

 foot, 19-5; ear from crown, 12. Skull — Total length, 24-8; basilar 



