28o MERRIAM 



Measurements. — Type specimen ( (? ad.): total length 2SS mm.; 

 tail vertebra 153; hind foot 37.5. Average of 7 adult males from 

 type locality: total length 295; tail vertebriE 163; hind foot 37.3. 

 Average of 2 adult females from type locality: total length 287; 

 tail 155; hind foot 33.7. 



ORYZOMYS COZUMEL^ sp. nov. 



Type from Cozumel Island, Yucatan, Mexico. No. 10S462 $ ad. 

 U. S. National Museum, Biological Survey Coll. April S, 1901. E. 

 W. Nelson and E. A. Goldman. Original number 14666. 



Characters. — Size large; similar to O. aquaticus.ihut darker; ears 

 and hind feet larger ; tail much longer and much darker. 



Color. — Upperparts dark grayish bister with pale fulvous suffusion 

 on sides and rump ; in old pelage back (es^Decially rump) rusty red ; 

 underparts varying from soiled whitish to pale buffy salmon; ears 

 dark brown, darkest on outer half; tail dusky, paler below. 



Cranial characters. — Skull large and heavy, with strongly marked 

 superciliary beads, long rostrum, and long incisive foramina. Closely 

 related to aquaticzis^ from which it differs in the following characters : 

 anterior roots of zygomata more depressed and less spreading; orbital 

 angle of frontal less marked ; posterior part of braincase broader, car- 

 rying the lateral beads outward posteriorly, so that they form almost 

 a straight line from side of occiput to angle of orbit ; incisive foramina 

 longer and more open. 



Re7narks. — Compared with aqiiaticus., the only species to which 

 it bears any near resemblance, the color in fresh pelage is grayer and 

 darker (less golden fulvous) ; in worn pelage redder — the rump and 

 hinder part of back more rusty ; ears and face darker, the face strongly 

 grizzled with black hairs. The underparts are never buffy yellow as 

 in aquaticus. 



AIeasure?fients. — Type specimen ( $ ad.) : total length 333 mm. ; 

 tail vertebrae 182; hind foot 35. Average of 5 adults from type lo- 

 cality: lotal length 315 ; tail vertebrae 1 76 ; hind foot 34.5. 



ORYZOMYS FULGENS Thomas. 



Oryzomys ftilgens Thomas, Ann. & Mag. Nat. Hist. (6), xi, 403-404, May, 

 1893. 



Type locality. — Mexico, exact locality unknown. Collected by A. 

 Boucard in southern Mexico, probably in or near the Valley of 

 Mexico. 



