1 900.] Allen, On Mammals Collected in Southeastern Peru. 223 



the young specimen the pelage of the ventral surface is plumbe- 

 ous for the basal two thirds of its length. (Cf. Thomas, under 

 IV. spinosustenuipes, in Ann. and Mag. Nat. Hist., yth Ser., V, Jan. 



These specimens agree so exactly with Mr. Thomas's original 

 description (P. Z. S., 1882, 105) of this species, from Huambo 

 examples, that their specific identity seems obvious, except that 

 the fifth hind toe, exclusive of the claw, reaches to the end of the 

 first phalanx of the fourth toe, instead of " barely to the middle 

 of the first phalanx of the fourth toe." The only mammae dis- 

 coverable in the female are 4, two pectoral and two abdominal. 



" All taken at the same place, under the edge of a bluff on a 

 small gulch. When the skin is fresh the spines on the back come 

 out very easily. I call this mouse Porcupine Mouse." H. H. K. 

 9. Oxymycterus juliacae, sp. nov. 



Type, No. 15804, $ ad. Juliaca, Peru, Nov. 29, 1899 ; coll. H. H. Keays. 



Above dark chestnut brown, grizzled with black, darkest along the median 

 line, where over a portion of the middle of the back the prevailing color is 

 black ; sides lighter and more reddish ; below dull brownish gray, with a faint 

 tinge of buff, well defined from the reddish brown color of the sides ; chin dull 

 yellowish white ; ears pale brown, well clothed on the inner surface with dusky 

 hairs, nearly naked externally ; upper surface of fore and hind feet blackish 

 brown, the palms flesh color, the soles darker, more brownish ; tail unicolor, 

 dark brown, sparsely clothed with short bristly black hairs, scarcely at all 

 concealing the annulations. 



Measurements. Total length, 250 mm.; head and body, 138; tail, 112; hind 

 foot, 32, without claws, 29; ear (in dry skin), 13, from notch, 16. 



Skull. Nasals broadest in front, slightly trumpet-shaped or flaring upward 

 at the end, and terminating posteriorly in a line with the lachrymals. The 

 rostral portion of the skull is broad in proportion to the rest of the skull, which 

 is rather narrow and elongate. Anterior zygoma-root low, narrow, and much 

 rounded off on the antero-superior border. Interorbital region with rounded 

 borders, and an incipient muscular ridge running from the orbit posteriorly. 

 Interparietal very small. Palatal foramina rather large, terminating posteriorly 

 in a line with the end of the first third of m 1 . 



Total length, 36.4; basilar length, 29; zygomatic breadth, 16; least interor- 

 bital breadth, 6.7; mastoid breadth, 14.8; nasals, 15; interparietal, 2x5.5; 

 diastema, 8; palatal foramina, 7.8x3; upper molar series, 8. 



The type and only specimen is an adult male in fine condition, 

 with the teeth much worn, showing it to be an old adult, yet 

 there is barely a suggestion of parietal ridges, and no trace what- 

 ever of any postorbital processes. 



