302 



VERTEBRATE ANIMALS OF THE UNITED STATES 



elevated above the ground in weeds or bushes and, raise from 3 to 7 

 young in a Htter and several litters a year. They resemble the house- 

 mouse in appearance, but may be distinguished by the browner colors, 

 more hairy tail and grooved upper incisors. 



Key to the Species of Reithrodontomys 



ai Tail less than 65 mm. long. 



bi Upper parts blackish or dark brown R. humulis. 



hi Upper parts grayish or buff, mixed with black, with a distinct 



dorsal stripe R. albescens. 



3.2 TaQ more than 65 mm. long, 

 bi Ears light brown or drab. 



Ci In the western and Pacific States R. megalotis. 



C2 On Catalina Island R. catalince. 



C3 In Texas, Louisiana and northwards R. fulvescens. 



bo Ears blackish brown; in western California R. raviventris 



R. humulis (Audubon & Bachman) (Fig. 162). Eastern harvest 

 mouse. Color dark brown above mixed with pinkish cinnamon, darker 

 on the head and middorsally; whitish beneath; length 120 

 f^mj, mm.; tail 57 mm.; hind foot 16 mm.: southern States. 



R. h. humulis (Aud. & Bach.). Ear 9 to 10 mm. long: 

 F'') i|\|| coastal plain from Virginia to central Florida. 

 i -I'll R. h. impiger Bangs. Ears smaller: mountains of 



// il'li northern Virginia and West Virginia. 



^,^„ R. h. merriami Allen. Ears smaller; under parts darker: 



.^, central Kentucky to central Alabama and westward to the 



^\i east Texas coast. 



^"^ R. albescens Gary. Color very pale; length 125 mm.: 



South Dakota to central Texas. 



R. ?negalotis (Baird) (Fig. 161) . Western harvest mouse. 

 Color brownish buff on the back and buff on the sides; 

 white beneath and on the feet; length 140 mm.; tail 71 

 mm.; hind foot 17 mm.; ear 12 mm.: western States to the 

 Pacific; southward into Mexico. 



ReuitlTd^- Subspecies of R. megalotis _ 



(after Stone R- w. megalotis (Baird). Southern Idaho southward 

 b'^Cram). ^^ eastern California and the Mexican border; then east- 

 ward to southwestern Texas. 

 R. m. aztecus Allen. Ears and skull larger: northern New Mexico, 

 northeastern Arizona, southeastern Utah and western Colorado. 



