1914.] 



BEITHEODONTOMYS MEGALOTIS GROUP. 



35 



REITHRODONTOMYS MEGALOTIS PENINSULA Elliot. 



Peninsula Harvest Mouse. 



RUthrodontomys peninsulse Elliot, Pub. Field Columb. Mus., Zool. Ser., Ill, 1903, 

 p. 164. 



Type locality. — San Quintin, Lower California. 



Distrihution. — West coast of Lower California, between latitude 30° 

 and 31°; southern limit of range not definitely kno-wTi. 



Characters. — Similar to longicaudus y but with larger ears and 

 longer tail. 



Color. — Fresh pelage (October to January): Similar to corre- 

 sponding pelage of longicaudus, but averaging richer and redder, and 

 less bro\\Tiish on the back; underparts wliite with a tinge of ochraceous- 

 buff. Worn summer pelage: Specimens not appreciably different from 

 longicaudus in same pelage. 



SJcull. — Similar to those of megalotis and longicaudus. 



Measurements. — Average of 11 specimens (adult and subadult) 

 from type locality: Total length, 154 (140-170); tail vertebrae, 84 

 (78-91); hind foot, 17.4 (16-18). Skull: (See table, p. 81). 



Remarlcs. — This form has a rather restricted range on the Pacific 

 coast of Lower CaHfornia. It is closely related to longicaudus, with 

 which it intergrades in the vicinity of San Telmo. 



Specimens examined. — Total number, 32, from the following locali- 

 ties: 



Lower California: Pozo Luciano (northwest slope San Pedro Martir Moun- 

 tains), 1; Rosario, 20;^ San Quintin, 8; San Telmo, 1; Socorro, 2. 



REITHRODONTOMYS MEGALOTIS CINEREUS Merriam. 

 Ashy Harvest Mouse. 

 Reithrodontomys saturatus cinereus Merriam, Proc. Wash. Acad. Sci., Ill, 1901, p. 556. 



Type locality. — Chalchicomula, Puebla, Mexico. 



Distribution. — Southern portion of Mexican table-land in the States 

 of Hidalgo, Puebla, and Tlaxcala. 



Characters. — SHghtly larger and darker than megalotis with much 

 darker ears and tail; paler than saturatus. 



Color. — ^Upperparts mixed black and light ochraceous-buff ; darkest 

 in the median line where the black sometimes appears as a broad 

 band; sides light ochraceous-bufi ; underparts grayish white with a 

 tinge of ochraceous-buff and sometimes with one or more small 

 blotches of the same color, chiefly in the pectoral region; ears fuscous, 

 with a large blackish patch' on the inferior inner margin and another 

 on the superior outer margin; tail, fuscous, darker than in megalotis . 



SlcuU. — ^Practically the same as that of saturatus, possibly a httle 

 shorter. 



1 Including 9 from Collection Mus. Comp. Zool. 



