DESCRIPTION OF A NEW SPECIES OF MOUSE (SITOMYS 

 DECOLORUS) FROM CENTRAL AMERICA. 



Bv 

 Frederick W. True, 



Curator of the Department of 3fammals, 



Among some specimens of mammals recently collected by Mr. E. 

 Wittkugel in Honduras for the National Museum, is a species of 

 /S'i^omys, belonging to the subgenus Rhipidomys {=N'yctomys Saussure), 

 which appears to be undescribed. Dr. J. A. Allen has already made 

 mention of a specimen of this species,* which specimen he regarded as 

 the young of tS. sumichrasii. He has kindly sent it to me for exami- 

 nation. It is an imperfect skin of a youngish individual, collected at 

 Santo Domingo, Tehuantepec, Mexico, by Dr. A. C. Buller. The tail 

 is wanting. It appears to agree in every respect with the Honduras 

 specimen in the National Museum, from which the following description 

 is taken. 1 may say incidentally that we have in the museum the skin of 

 a young S. suniicJirasti, which shows the closest possible similarity to 

 the adults of that si)ecies. 



The following is a description of Wittkugel's Honduras specimen, 

 No. 21092, from Eio de las Piedras, collected Dec. 11, 1890: 



Sitomys (Rhipidomys) decolorus, sp. nov. 



Size intermediate between Mus musculns and M. decumanus. Ears 

 prominent, thin, nearly naked. Soles naked, except in the proximal 

 fourth, the naked portion not granular, and with prominent pads. 

 Tail clothed with longish hairs, growing more abundant toward its tip, 

 where they conceal the scales and form a pencil. 



Color above brownish-isabelline, more or less shaded with gray 

 along the middle of the back. Flanks clearer. Under surfaces and 

 lower part of cheeks pure white, not blending with the color of the 

 sides. Feet like the back, but the hinder ones somewhat more dusky. 

 Toes impure white. Ears sparsely clothed with rather long, choco- 

 late-brown bairs externally, and similar, but somewhat lighter-col- 

 ored, hairs internally. Hairs of the tail chocolate-brown, not lighter 



* Bull. Amer. Mu8. Nat. Hist., in, 1890, 187. 

 Procet'dings National Museum Vol. XVI— No. 963. 



Proc. N. M. 93 44.- 689 



