OCT., 1915. MAMMALS FROM BRAZIL AND PERU OSGOOD. 191 



nearly vertical as in Phyllotis, not decidedly flexed forward in its lower 

 half as in Euneomys; palatal pits and foramina practically as in Phyllotis; 

 tail shorter than head and body as in Euneomys. 



Remarks: Some of the species of this group have been referred to 

 Phyllotis and others to Euneomys and it is clear that although they have 

 affinities to both, they should have some collective recognition. On 

 the whole, they have more of the characters of Phyllotis than of Eune- 

 omys and it seems best therefore to regard the group as a subgenus of 

 Phyllotis. The species referable to it with certainty are: Phyllotis 

 sublimis Thomas, P. pictus Thomas, P. boliviensis Waterhouse, P. b. 

 ftavidior Thomas, and P. decoloratus sp. nov. 



Phyllotis (Auliscomys) decoloratus sp. nov. 



Type from Tirapata, Dept. Puno, Peru. No. 16500 American 

 Museum of Natural History. Adult female. Collected October 21, 

 1900, by H. H. Keays. 



Characters: Similar to Phyllotis pictus but smaller and paler; 

 somewhat similar to P. boliviensis but decidedly smaller, especially the 

 ears and feet, and with the color of the ears and the rump more con- 

 trasted with that of the body. General distribution of color practically 

 as in P. pictus but paler throughout, the rump inclining to buffy rather 

 than tawny, the head and shoulders a paler grayish and the feet entirely 

 white without traces of ochraceous; inside of ears pale ochraceous buff 

 well-contrasted with the surrounding grayish, but much paler than the 

 rich tawny of P. pictus. 



Skull decidedly smaller and relatively narrower than that of P. 

 pictus; upper incisors distinctly grooved and rather pale in color. 



Measurements: Type and adult male topotype, respectively: 

 Total length 178, 216; head and body 95, 114; tail 83, 102; hind foot 23, 

 25; ear from notch (dry) 17, 18. Skull of type: Greatest length 26.6; 

 basilar length 20.9; zygomatic breadth 15.4; least interorbital breadth 

 4.2; nasals 10.4x4; breadth of braincase 12.6; diastema 7; palatine 

 foramina 6.4X2; upper toothrow 5.1. 



Remarks: I am indebted to Dr. J. A. Allen for the privilege of 

 examining the type and several additional specimens of this species from 

 the collection of the American Museum of Natural History. These 

 were at first supposed to represent P. boliviensis, but examination of the 

 original description of that species in connection with a topotype 

 kindly loaned by Mr. G. S. Miller, Jr., of the United States National 

 Museum indicates that this is far from the case. P. boliviensis, as 



