RICE RATS 295 



Measurements. — Type specimen ( $ yg.-ad.) : total length 235 

 mm.; tail 119; hind foot 32. 



ORYZOMYS FULVESCENS (DeSaussure). 



Hesperovtys fulvescens DeSaussure, Rev. et Mag. Zool., xii, pp. 102-103, 



March, i860. 

 Oryzo77iys fulvescens Allen, Bull. Am. Mus. Nat. Hist., N. Y., ix, p. 204, 



June, 1897. 



Type locality. — Unknown. Collected by Sumichrast, probably in 

 the vicinity of Orizaba, Vera Cruz, which is here fixed as the type 

 locality. 



Characters. — Size smallest of the known species, with much the 

 appearance of the smaller species of Reithrodontomys ; color, includ- 

 ing underparts, yellowish fulvous; skull small, thin, and papery, 

 about the size of that of the common house mouse, and suggesting the 

 smallest species of Reithrodontomys. 



Color. — Upperparts yellowish fulvous, copiously lined with black 

 hairs; underparts bright and rather intense yellowish fulvous; chin 

 and throat paler. In immature specimens the belly is sometimes 

 whitish. 



Cranial characters. — Skull small and thin, without trace of supra- 

 orbital bead ; braincase swollen and smoothly rounded ; zygomata 

 slender, almost threadlike, weak anteriorly; incisive foramina short 

 and broadly open ; nasals rather small, ending about on plane with 

 premaxillae. 



Remarks. — This tiny species has a very extensive distribution, 

 ranging over considerable parts of Vera Cruz, Oaxaca, Guerrero, 

 Chiapas, Yucatan, and Guatemala. 



