124 Merriam New Mice from Mexico and Guatemala. 



Cranial characters. Skull resembling that of P. gratus, but larger, brain- 

 case flatter ; zygomata more spreading and less notched by anteorbital 

 slit; rostrum heavier as seen from below ; audital bullae smaller; nasals 

 longer. 



Measurements. Type specimen: Total length 200; tail vertebrae 102; 

 hind foot 23.5. 



Peromyscus hylocetes sp. nov. 



Type from Patzcnaro, Michoacan, Mexico (alt. about 8000 ft.). No. 

 50423, ? ad., U. S.Nat, Mus., Biological Survey Coll. Collected July 

 27, 1892, by E. W. Nelson and E. A. Goldman. Orig. No. 2961. 



Characters. Size medium ; ears medium ; tail shorter than head and 

 body well haired and sharply bicolor. Color grayish. 



Color. Upperparts buffy gray becoming buffy ochraceous on sides and 

 with a broad dark dorsal area resulting from bountiful admixture of black 

 hairs; underparts, lips, and fore feet whitish ; wrists and ankles dusky, 

 the color of latter spreading over basal part of hind foot; tail dusky 

 above, white below. 



Cranial characters. Skull rather broad and short, with moderately 

 spreading zygomata and no supraorbital beads ; braincase rather full and 

 broadly rounded ; audital bullse smaller than in the truei-difficilis group, 

 but larger than in mexicanus and slightly larger than oaxacensw. 



Measurements. Type specimen: Total length 238; tail vertebrae 114; 

 hind foot 25. Average of 3 specimens from type locality : Total length 

 232; tail vertebra 112; hind foot 26 



Peromyscus musculoides sp. nov. 



Type from Cuicatlan, Oaxaca, Mexico (alt. 1800 ft.). No. 69661, $ old, 

 U. S. Nat. Mus., Biological Survey Coll. Collected Oct. 14, 1894, by E. W. 

 Nelson and E. A. Goldman. Orig. No. 6892. 



Characters. Size a little larger than Mus musculus, which it greatly re 

 sembles; pelage short, close and rather coarse; ears rather short; tail 

 shorter than head and body, moderately haired, bicolor. 



Color. Upperparts drab gray, becoming brownish on sides ; underparts, 

 lips and sides of nose milk-white; ankles dusky; fore and hind feet 

 white; tail brownish above, whitish below. 



Cranial characters. Skull small ; braincase rounded ; frontals broad be 

 tween orbits but without trace of ' bead ' ; zygomata strongly notched by 

 anteorbital slits ; audital bullae small. 



Measurements. Type specimen: Total length 187; tail vertebrae 88; 

 hind foot 22.5. Average of 10 specimens from type locality : Total length 

 185 ; tail vertebrae 84.5 ; hind foot 22.5. 



Peromyscus mekisturus sp. nov. 



^efrom Chalchicomula, Puebla, Mexico (alt. 8400 ft.). No. 64108, 

 ? ad., U. S. Nat. Mus., Biological Survey Coll. Collected March 16, 

 1894, by E. W. Nelson and E. A. Goldman. Orig. No. 5951. 



