RICE RATS 285 



Cranial characters. — Skull similar in general to that of inexicatius 

 but narrower and lighter, with much slenderer zygomata and less dis- 

 tinct superciliary beads; molars decidedly smaller. 



Remarks. — Externally jalapce resembles mexicanus rather closely 

 in size and color, but it is easily distinguished by its much larger ears 

 and smaller hind feet, and also by the strong fulvous underparts, the 

 underparts in mexicanus being white or buffy. The cranial differ- 

 ences have been already pointed out. O. jalapce is common in most 

 parts of the State of Vera Cruz and in parts of northwestern Puebla. 



MeasureTiients. — Average of 6 specimens from Orizaba, Oaxaca : 

 total length 266 mm. ; tail vertebras 140.5 ; hind foot 31. 



ORYZOMYS JALAPS RUFINUS subsp. nov. 



Type from Catemaco, Vera Cruz, Mexico. No. 65499 ? ^^* U. 

 S. National Museum, Biological Survey Coll. April 27, 1894. E. 

 W. Nelson and E. A. Goldman. Original number 61 12. 



Characters. — Similartoya/a/^ but back, and especially rump^ much 

 redder^ the color intense fulvous ; tail dusky all round., the underside 

 even to very base being dark, and the white hairs smaller and less 

 abundant; incisors heavier than \xi jalapce ; molars in female (type 

 specimen) as large as in the largest male oi jalapce. 



Measure77ients. — Type specimen ($ ad.): total length 270 mm.; 

 tail 139; hind foot 32. 



ORYZOMYS ZYGOMATICUS sp. nov. 



Type from Nenton, Guatemala. No. 76794 $ ad. U. S. Na- 

 tional Museum, Biological Survey Coll. Dec. 15, 1895. E. W. 

 Nelson and E. A. Goldman. Original number 879S. 



Characters. — Size and ears medium ; color dull fulvous ; size and 

 external appearance much as in jalapce but hind feet larger ; ears 

 slightly smaller; underparts much paler; skull characters distinctive. 



Color. — Upperparts dull pale fulvous, conspicuously lined on middle 

 of back with black hairs ; underparts in type specimen white with 

 slight buffy suffusion, strongest between forelegs ; in younger speci- 

 mens suffusion deeper. 



Cranial characters. — Skull similar in size and general form to 

 jalapce^ but superciliary ridges much more stro7igly developed and 

 everted; nasals narrower on middle and posterior thirds ; zygomata 

 strongly and evenly bozued 02itzuard and dowmvard., sinking far be- 

 low level of posterior root — instead of approximating and sloping 

 forward and upward from posterior root as usual. 



