24 



NOETH AMEEICAN FAUNA. 



[No. 36. 



Angelo, Tex. : 142 ; 60 ; 15. Average of 8 (subadult) from Alva, Okla. : 

 117; 51.5; 16. Skull: (See table, p. 81). 



Remar'lcs. — Although clearly belonging in the same group with 

 R. Tiumulis merriami, this form appears not to intergrade with it. In 

 both skin and skuU characters it agrees closely with albescens and 

 differs widely from merriami, its nearest relative geographically. 

 Specimens from Kansas and Oklahoma and one from Santa Kosa, 

 N. Mex., can not be distinguished from typical examples. 



Specimens examined. — Total number, 82, from the following locali- 

 ties: 



Nebraska: London, 2. 



Kansas: Onaga, 18; Pendennis, 5; Trego County, 10. 

 Oklah-oma: Alva, 12.^ 



Texas: Clyde, 1; Gainesville, 1; Mason, 9; San Angelo, 1; San Antonio, 22. 

 New Mexico: Santa Rosa, 1. 



REITHRODONTOMYS MEGALOTIS GROUP. 



REITHRODONTOMYS MONTANUS (Baird). 

 San Luis Valley Harvest Mouse. 

 (PL I, fig. 5; PL IV, fig. 5.) 



Reithrodon montanus Baird, Proc. Acad. Nat. Sci. Phila., VII, 1855, p. 335; Mamm. 



N. Am., 1857, p. 449. 

 Ochetodon montanus Coues, Proc. Acad. Nat. Sci. Phila., 1874, p. 186. 

 Reithrodontomys montanus Allen, Bull. Am. Mus. Nat. Hist., V, 1893, p. 80; VII, 



1895, p. 123; Caiy, N. Am. Fauna No. 33, 1911, p. 108. 



Type locality. — ''Eocky Mountains, latitude 38°" [upper end San 

 Luis Valley, Colo., near San Luis Lakes]. 

 Distribution. — San Luis Valley, Colo." 



CJiaracters. — Size medium (smaller than R, m. megahtisj larger 

 than R. a. griseus); ears small; color slightly paler and less ochra- 

 ceous than in megalotis; skull similar to that of megalotis but smaller 

 and narrower. Compared with R. a. albescens and R. a. griseus: 

 No distinct blackish dorsal stripe; skull relatively longer and nar- 

 rower; tail slightly longer. 



Color. — Fresli winter pelage (October and November) : Light buff, 

 clearest on sides and face, much mixed with blackish on dorsal sur- 

 face; black hairs most pronounced on hinder back; no distinct 

 median line of black; ears dark hair-brown, often clothed on inner 

 surface with ochraceous-buff hairs (a Httle darker than body hairs), 

 rarely with a distinct blackish area on lower outer margin; tail dis- 

 tinctly bicolor, dark hair-brown above, white beneath; feet and 

 underparts white. Compared with megalotis, the general tone is paler 

 and less intensely ochraceous; the sides hght buff instead of ochra- 

 ceous-buff. 



1 Collection Field Mus. Nat. Hist. 



