HETEROMYID^ 153 



The only vocal sounds that I have heard from adults are 

 squeaks of pain when caught in a trap or otherwise hurt. The 

 greater number of young are born in the spring, but reproduc- 

 tion continues to some extent through the summer and autumn. 

 Three to five young at a birth appear to be the usual number. 



Pocket-Rats make interesting pets. They do not resent be- 

 ing handled, though not really liking it. They do not often try 

 to escape when held in the hands. They require considerable 

 provocation and rough usage before attempting to bite. As they 

 can open the mouth but a short distance and the upper incisors 

 are bent backwards they are unable to bite deeply, scarcely more 

 than through the skin. They keep in good health in captivity 

 on grain alone. They do not bear cold well. 



Perodipus ingens Merriam. 



BIG POCKET-RAT. 



Size large ; above buffy ochraceous ; tail with upper and lower 

 stripes black and a white pencil ; ears small ; skull very large and 

 massive. 



Length about 350 mm. (13.75 inches) ; tail vertebrae 190 

 (7.50) ; hind foot 52 (2.05). 



Type locality, Painted Rock, San Luis Obispo County, Cali- 

 fornia. 



Known only from the Carrizo Plain. 



Perodipus venustus Merriam. (Beautiful.) 



SANTA CRUZ POCKET-RAT. 



Similar to agilis, but very much darker; top of head, back, 

 and Lhigh patches dusky, finely grizzled with ochraceous; hairs- 

 of rump forming a black patch just in front of basal white ring: 

 of tail. 



Length about 315 mm. (12.40 inches) ; tail vertebrae 190 

 (7.50); hind foot 45 (1.77). 



Type locality, Santa Cruz, California. 



Santa Cruz and Santa Lucia Mountains. 



