1899-] Allen, Five New American Rodents. 15 



Reithrodontomys tenuis, sp. nov. 



Similar to Reithrodontomys fulvescens, but much smaller and not so gray, 

 with a much less hairy tail. 



Above yellowish brown, finely lined with black ; sides fulvous, forming a 

 broad lateral line, poorly defined above, very prominent on the cheeks below 

 the eyes. Below soiled grayish white (in one specimen slightly tinged with 

 fulvous), the hairs pale plumbeous at base. Ears dusky externally, reddish 

 within, covered with fine short hairs, with a reddish tuft at the anterior base. 

 Tail grayish brown, slightly darker above than on the sides and below. Feet 

 soiled white. 



Total length (collector's measurements) of type, 152 mm. ; tail, 81 ; hind 

 foot, 20 ; ear, 15. Three specimens (2 $ $ , i $) measure : Total length, 160 

 (152-170) ; tail, 87 (82-90) ; hind foot, 20 ; ear, 15. 



Type, No. 217, Coll. W. W. Price, $ad., Rosario, Sinaloa, Mexico, March 

 II, 1897. Collected by P. O. Simons. (Type in British Museum.) 



This species is more nearly related to my R. fulvescens, from 

 Oposura, Sinaloa, Mexico, than to any other yet described. It 

 is, however, much smaller, being intermediate in size between 

 this species and R. longicauda, the total length being 160, and the 

 length of tail 87, as against 176 and 100, respectively, in R. ful- 

 vescens. The general coloration is also more strongly fulvous 

 above, particularly posteriorly, and there is a tendency to a 

 fulvous tinge below in contrast with the clear white of the lower 

 parts in R. fulvescens. It needs no comparison with any member 

 of either the R. mexicanus or R. longicauda groups. The skull 

 presents nothing diagnostic. 



I am indebted to Mr. Oldfield Thomas for the opportunity to 

 examine the three specimens on which this species is based. 



Peromyscus texanus subarcticus, subsp. nov, 



Peromyscus leucopus arcticus ALLEN, Bull. Am. Mus. Nat. Hist. VII, 1895, 

 268 ; ibid. VIII, 1896, 252. (Not arcticus of Mearns.) 



Intermediate in size and coloration between P. texanus nebrascensis and P.. 

 texanus arcticus but very different from either. 



Above dusky brown suffused with very pale fulvous, darker and more blackish 

 over the middle of the back, more fulvous on the sides ; feet and lower parts 

 pure white ; tail sharply bicolor, the middle third above blackish brown ; sides 

 and beneath white ; ears dusky, narrowly edged with white. 



Total length (of type), 165 ; tail vertebrae, 66 ; hind foot, 19. Average of 

 three specimens from the type locality (Deerlodge Co., Montana), total length, 

 162 ; tail vertebrae, 61 ; hind foot, 19.2. 



Type, ^Vrr. ? ad - Au S- I 3> l8 94- Collected by Prof. L. L. Dyche. 



