MAMMALS OF THE MEXICAN BOUNDARY. 



379 



under surface, feet, and end of tail, white. Average measurement.s of 

 two adult females: Length, 154 nun.; tail vertebrge, 56.5; ear from 

 crown, 15; length of hind foot, 21.3. Skull (fig. 66), 26.3 by 13.5. 



A young male (No. 60815, U.S.N.M.), about two -thirds grown, 

 taken at Seven Wells, on the Colorado Desert, in I^ower California, 

 measured 128 mm. in length, with the tail vertebrae 50, ear from 

 crown 14, and hind foot 21. Above, it is smoke gray. The ear shows 

 a distinct dusk}^ spot of mouse gray, and the terminal third of the tail 

 is all white. 



Measurements of .5 speeimrns Onychomys torridiis prrpallidus. 



"Contained 4 large fetusi^s. 



h Type. 



ONYCHOMYS TORRIDUS RAMONA (Rhoads). 

 RAMONA GRASSHOPPER MOUSE. 



Onychomys ramona Riioads, American Naturalist, XXVII, p. 833, Sept., 1893 (original 



description). — Miller and Reiin, Proc. Bost. Soc. Nat. Hist., XXX, No. 1, Dec. 



27, 1901, p. 67 (Syst. Results Study N. Am. Mam. to close of 1900). 

 [Oni/cJiomys] ramona . Elliot, Field Ool. Mus., Zool. Ser., II, 1901, p. 121 (Synop. 



Mam. N. Am.). 

 0[jiychomys] ramona, Elliot, Field Col. Mus., Zool. .Ser., IV, 1904, pp. 165, 167 (Mam. 



Mid. Am.). 



Description. — Size of typical Onychomys forridus but very much 

 darker in color. Proportions about the same as those of torridus. 

 Upper surface drab, tinged with cinnamon on sides, and much mixed 

 with black on top of head and vertebral area; lanuginous tufts at base 

 of ear soiled grayish white; ears blackish, edged with white apically; 

 upper side of tail blacldsh nearly to the tip; whiskers mostly black; 

 under surface, feet, and extreme tip of tail, white. Average measure- 

 ments of two adults, male and female: Length, 143 mm.; tail verte- 

 brae, 51.5; ear above crown, 14; length of hind foot, 20.5. Skull, 25 

 by 13. 



Two gray-pelaged young, collected bj" Mr. Holzner, May 21 and 25, 

 at the foot of the Santee Mountains, San Diego County, California, 

 have the upper surface mouse gray, and the ears nearh^ black. They 

 are the darkest specimens seen of this species. 



