562 MERRIAM 



over orbits and reach posteriorly to occiput, as in Tylomvs, but differ- 

 ing from Tylomys in the following characters: 



1. Bulhe rotate-capsular, inflated, as broad anteriorly as posteriorly, 

 without narrow anterior prolongation ; axes essentially parallel to axis 

 of skull. Similar to those of Xenoifiys but smaller. 



2. Anterior or maxillary root of zygoma strongly notched above (at 

 base of rostrum) as in Peromysczts and Xenomys. 



3. Outer lip of anterior opening of antorbital vacuity vertica/ us in 

 Neotofua and Pe7-omyscus^ not concave as in Tylotuys. 



4. Fossa at base of rostrum less developed. 



5. Incisive foramina enormous, as broadly open anteriorly as pos- 

 teriorly. 



6. Angle of jaw excavated posteriorly, leaving a sharp point pro- 

 jecting backward as in Pcromyscus^ the infracondyloid notch corre- 

 spondingly long and deep (differing widely from the broadly ex- 

 panded and rounded angle of Tylomys^ which is convex posteriorly 

 instead of sharply concave). 



7. Coronoid process reduced to a mere point as in Perornysciis ; 

 postcoronoid notch flat and nearly horizontal. 



OTOTYLOMYS PHYLLOTIS sp. nov. 



Type from Tunkas, Yucatan. No. 108099. $ old, U. S. National 



Museum, Biological Survey Coll. Feb. 17, 1901. E. W. Nelson 



and E. A. Goldman. Orig. no. 1455 1. 



Characters. — Size of Mus rattus (equaling the smaller species of 

 Neotoma')\ ears enormous and leaf-like; tail long (as long as head 

 and body), naked, the annulations and scales broad. General ap- 

 pearance as in Tyloviys but size smaller, ears much larger, upperside 

 of tail dark throughout (terminal half not yellow). 



Color. — Upperparts varying fiom grayish blown to very dull ful- 

 vous brown, in some specimens conspicuously mixed with black-tip- 

 ped hairs; underparts, including inner side of fore and hind legs, 

 white or buffy white; ankles and wrists dark: fore and hind feet 

 whitish ; face brownish or grayish, washed on cheeks and around 

 ej^e with pale fulvous; tail brownish dusky above, irregularly yellow- 

 ish beneath. Young grayish plumbeous with top of head (from be- 

 tween eyes posteriorly) and middle part of back darker. 



Cra?zial characters (additional to generic characters already given). 

 — Rostrum long and slender; nasals long and slender; their sides 

 nearly parallel, truncate posteriorly about on plane of premaxillae ; 

 zygomata moderately spreading, broadest joosteriorly ; interparietal 



