114 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 69 



Contrasted with 1/ dariensis this species seems to be smaller. It 

 is similar in the general character of its pelage, bu! differs otherwise 

 in about the same t harai ten as M. cavator. 



Specimens examined : Bugaba, 6* (including type). 



Family HETEROMYIDAE. Pocket Mice 



The pocket mice are small rodents at once distinguishable by the 

 deep external cheek punches in combination with spiny or bristly 

 pelage. In the character of the pelage they are not very unlike the 

 Murine genus Neacomys, but the cheek pouches are distinctive. Two 

 genera, Heteromys and Li amy s, inhabit the region under review. 



Subfamily HETEROMYINAE. Pocket Mice 

 Genua HETEROMYS Desmarest. Pocket Mice 

 Externally the pocket mice of this genus closely resemble those 

 of the genus Lioitt\<s, bu1 are more blackish, less grayish in the color 

 of the upper parts, and the sole of the hind foot in the Pan. una iKnns 

 is naked to the heel. The generic characters are exhibited by the 

 skull, the dentition being more complex, the interpterygoid fossa 

 V-shaped instead of U-shaped, and the angle of the mandible much 

 less strongly everted than in the genus Liomys. 



Subgenus HETEROMYS Desmarest 



HETEROMYS AUSTRALIS CONSCIUS Goldman 



I .iii.i Pocket Mouse 



1 1 Mate 25, figs. 4, 4a] 



Heteromys australis consdtU Goldman, Smiths. Misc. Coll., Vol, 60, No. 22, 

 pp. 8-9, February 28, 1913. Type from Cana, eastern Panama (.tltitude 

 2,000 feet). 



H. a. conscius is a small form of the genus, a rather slightly 

 differentiated northern offshoot of the Ecuadorean species H. aus- 

 tralis, which belongs to the Heteromys um> mains group. It is 

 similar externally to some of the other forms of the region, but the 

 cranial characters are distinctive. It is darker in general color than 

 H. a. australis, and the slender hairs aiming the bristles on the back 

 are grayer than in //. a. lomitensis, a closely allied Colombian form. 

 The skull is more elongated, with broader ascending branches of 

 premaxillae than that of H. a. australis; from that of H. a. lomitensis 

 it differs in the broader upper surface of the maxillary arm of the 



1 Collection Mus. Comp. Zool. 



