1899.] Allen, New Rodents from Colombia and Venezuela. 2OI 



from sea level to 500 feet. As usual in doubtless all the species 

 of Echimys, about one in four to six, in the adults, is tailless. 



In coloration Echimys canicollis appears to greatly resemble 

 Loncheres caniceps Giinther (P. Z. S., 1876, 745), from Medellin, 

 but here the resemblance ceases, the two forms being not even 

 -congeneric. 



It is very different in color from either of the three other 

 species mentioned in the present paper, and differs likewise in 

 cranial characters. In dentition it is quite similar to E. trinitatis, 

 E. minca, and E. itrichi, but the skull is relatively shorter and 

 broader, the audital bullse are very much larger, and the ptery- 

 goids much slenderer and very differently shaped, while the basi- 

 occipital region is greatly narrowed, in consequence of the unusual 

 -size of the audital bullse. It seems not to need comparison with 

 any of the other described species of the genus. 



Heteromys jesupi, sp. nov. 



Type, No. 15347, near Minca (at an alt. of loco ft.), Santa Marta District, 

 Colombia, July 30, 1899 ; Coll. H. II. Smith. 



Slightly larger than Heteromys anomalus. of Trinidad, and much paler. Gen- 

 eral color above grayish brown slightly varied with yellowish ; beneath pure 

 white, including the inner surface of the limbs, the white extending well up on 

 the sides and running forward along edge of the cheek pouches to the nose, as 

 in the allied forms,//, anomalus, H. melanoleuciis, and^. longicaudatus ; upper 

 surface of hind feet dull white ; of fore feet grayish white ; forearm grayish 

 brown, instead of blackish brown, as in the other forms ; tail and ears scaritily 

 haired. Mammae, y-j-f- 6, -' two pectoral and four inguinal. Soles naked, 

 6-tuberculate. 



Measurements. Type, total length, 330 mm. ; tail vertebrae, 163 ; hind foot, 

 33 ; ear (in skin), 16.3. 



Skull, total length, 31.5 ; basal length, 26 ; zygomatic width, 16 ; mastoid 

 width, 16 ; interorbital width, 8.6; crown length of upper toothrow, 4.5; 

 length of lower toothrow, 4.6. 



Named in honor of Morris K. Jesup, President of the Amer- 

 ican Museum of Natural History, through whose liberality the 

 Museum has been placed in possession of the extensive collection 

 of Colombian mammals which forms the basis of the present 

 paper. 



Heteromys jesupi is based on a series of 13 specimens, from six 

 different localities in the Santa Marta District, varying in eleva- 

 tion from sea level to 2000 feet, as follows : Bon da and Mam at oca, 



