PERODIPUS. 93 



Perodipus morroensis Merriam. 



Perodipus morroensis Merr., Proc. Biol. Soc. Wash., XX, 1907, p. 78. 



Type locality. Morro, San Luis Obispo County, California. 



Genl. Char. Similar to P. simulans but with smaller ears and 

 blacker nose-bar. Skull has a broad zygomatic arch, small mastoids 

 and slender incisors. 



Color. Spot on nose and whisker-patches jet black, forming a 

 bar across face; upperparts ochraceous-buff; tinged with olivaceous; 

 front of face grizzled buffy; top of head, like back; flanks clear ochra- 

 ceous-buff, rest of pelage white; thighs like back; limbs, hands and 

 feet white; tail above blackish brown on basal half, purplish brown 

 on remainder; sides white, beneath dark brown. Ex type in United 

 States National Museum. 



Measurements. Total length, 300; tail, 182; hind foot, 45. Skull: 

 Occipito-nasal length, 38.8; Hensel, 26.7; zygomatic width, 20; inter- 

 temporal width, 13.2; length of nasals, 13.8; palatal length, 9.6; 

 length of upper molar series, 5; length of mandible, 13; length of 

 lower molar series, 4.7. Ex type in United States National Museum. 



Perodipus Stephens! Merriam. 



Perodipus stephensi Merr., Proc. Biol. Soc. Wash., XX, 1907, p. 78. 



Type locality. San Jacinto Valley, Riverside County, California. 



Genl. Char. Like P. streatori, but with slight difference in skull. 

 Cranial shield broader posteriorly; mastoid bullae fuller, incisors 

 weaker. 



Color. Head and upperparts mixed black and ochraceous-buff, 

 black predominating; flanks ochraceous-buff, no black; black line 

 across face, curving down to end of nose; spot behind eyes, one behind 

 ears, lips, entire underparts, arms on outer and inner sides, inner 

 side of hind legs, hands and feet pure white; tail above blackish, 

 including tuft; sides white, beneath dark brown. Ex type in United 

 States National Museum. 



Measurements. Total length, 294; tail, 175; hind foot, 39. 

 Skull: Occipito-nasal length, 38.6; Hensel, 26.5; zygomatic width, 

 1 8. 6; intertemporal width, 12.4; length of nasals, 14.1; length of 

 upper molar series, 4.9 ; length of mandible, 14. 2 ; length of lower molar 

 series, 4.6. Ex type in United States National Museum. 



Perodipus simulans peninsularis Merriam. 



Perodipus simulans peninsularis Merr., Proc. Biol. Soc. Wash., 



XX, 1907, p. 79. 



Type locality. Santo Domingo, Lower California, Mexico. 

 Genl. Char. Similar to D. simulans but larger; general color paler; 



