Jferriam — JSTeir MunundU from (^nzinnel Tshnnl. 103 



Peromyscus cozumel« sp. iio\ . 



Tfipi from Cozumel Isltmd, ^'uoatan, Xo. 108,44'.), ^' ad., V. S. Xaiidual 

 Muspum. Hiologieal Survey Collection. Ajiiil 11. ISDl, K. W. Nelson 

 and E. A. Goldman. Original Xo. 14,()S(). 



Cliinutctcrx. — Size and tail medium; ears rallier large, lliin; color dull 

 brown <ir brownish fuhous: general appearaiu-e similar to P. affiiiis X\- 

 len,* bul sliuiilly lar.yer and somewhat darker and moi'e uiiirorm in 

 color. 



Ciihir. — Head and upperpai'ls varyinji I'rom grayish bruwn lo dull ful- 

 vous brown: underparts white, the iilumbeousunderfur showing through: 

 tail indistinctly bicolor, browni.sh dusky above, pale yellowish or whitish 

 below (nearly naked): ankles and wrists brownish or dusky: fore and 

 hiiul feet whitish. 



('/■toiii'l r/iiiriicfci'.s. — Skull of medium size, willi rather spreading zygo- 

 mata, strongly set out and angled anteriorly: nasals broad, flattened, 

 ending about on plane of premaxilhe: incisive foramina rather large and 

 open. 



EeiiKirkx. — Peroti/t/.'o'fix ciiziiintlii' appears to have no very close relative. 

 E.x'terually it resembles F. affinis Allen, but is darker and has thinner 

 ears and shorter tail. Cranially, however, it differs materially from any 

 species known to me. Compared with affinix it may be distinguished by 

 the broader and more s(pu\rely elbowed zygomata. Hatler and broader 

 braincase. broader nasals, slightly larger bulhe, and heavier teeth. The 

 incisive foramina show^ considerable variation. In most specimens they 

 are long- and their outer borders are evenly convex. In others they are 

 much nu)re broadly open and the outer bonier forms an angle at the 

 maxillo-premaxillary suture. In some specimens they are rather short. 



MrKsiireuii'ittn. — Type specimen ((j^ad.): total length 180: tail vertebrae 

 81): hind foot 2)5. Average of 8 males from type locality: total length 

 LSI: tail vertebra' 8->: hind foot 23.5. 



Oryzomys cozumela? s[). nov. 



TjijH' from Cozumel Island, Yucatan. Xo. 108,4()2. <^ ad., U. S. Na- 

 tional Museum. Biological Survey Collection. April 8. 1!>(»1, T']. W. Xel- 

 son and E. A. (ioklman. Original Xo. 14.()()(). 



('//iinirtcrs.- i^iy.e large; similar to (). iK/nn/irus Allen, but darker; 

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



Color. — T'pperparts dark grayish bister with pale fuhous sutt'usion on 

 sides and rump: in old pelage back (especially rump) rusty red; under- 



*My Peroinyxrun muftruloidei^ (Proc. Biol. Soc. Wash., Vol. XII, p. 124, 

 April ;{(). 18!)8) appears to be at most onlv a subspecies of P. ////?///,* Allen, 

 from which it differs in slightly larger size, larger ears and longer ros- 

 trum. 



