NO. 22 MAMMALS FROM PANAMA AND MEXICO GOLDMAN 9 



slender hairs among the bristles grayer than in the latter ; skull differ- 

 ing from those of both in various details, especially the greater 

 breadth of ascending branches of premaxillse. 



Color. — Ground color of upper parts dark blackish slate or slaty 

 black, the slender grayish hairs among the darker bristles giving the 

 dorsum a finely lined appearance; under parts, including lips and 

 inner sides of limbs, pure white; forearms whitish, more or less 

 mixed with grayish, especially along outer sides; ankles dusky all 

 round; feet grayish to toes, the toes white; tail brownish above, 

 somewhat lighter below, becoming dark all round toward tip. 



Skull. — Closely resembling that of H. a. australis, but more elon- 

 gated ; ascending branches of premaxillae broader. Contrasted with 

 that of H. a. lomitensis the upper surface of maxillary arm of zygoma 

 is broader, and the ascending branches of premaxillae are broader 

 posteriorly and more nearly conterminous with nasals (nasals reach- 

 ing farther posteriorly in H. a. lomitensis). 



Measurements.- — -Type: Total length, 260 millimeters; tail verte- 

 bras, 133; hind foot, 32. Average of 2 adult topotypes: 245 (240- 

 251); 125 (120-131); 32.2 (31-33-5)- Skull (type): Greatest 

 length, 34.7 ; zygomatic breadth, 16.5 ; interorbital breadth, 8.3 ; nasals, 

 14.4; width of braincase at anterior border of auditory meatus, 14.7 ; 

 interparietal, 8.7 x 5.3 ; maxillary toothrow, 5.4. 



Remarks. — This pocket mouse and the two South American 

 forms described as H. australis and H. lomitensis are all very closely 

 allied and may stand subspecifically as follows : 



Heteromys australis australis Thomas, San Javier, Ecuador. 



Heteromys australis lomitensis Allen, Las Lomitas, Cauca, Colombia. 



Heteromys australis consents Goldman, Cana, Panama. 



The form here described was the only pocket mouse found on the 

 lower slopes of the Pirri Range at from 1,800 to 2,000 feet altitude; 

 the upper slopes above 4,500 feet are inhabited by the very different 

 species, H. crassirostris. 



Specimens examined. — Five, all from the type locality. 



AGOUTI PACA NELSONI, new subspecies 

 Type from Catemaco, southern Vera Cruz, Mexico. No. 65952, 

 male adult, U. S. National Museum (Biological Survey Collection), 

 collected by E. W. Nelson and E. A. Goldman, April 30, 1894 

 Original number 6i35- 



Distribution. — Coastal plains and mountain slopes from the vicinity 

 of Jalapa, Vera Cruz, eastward and southward through Tabasco, 

 Chiapas and the peninsula of Yucatan to eastern Guatemala and 

 western Honduras. 



