NO. 5 MAMMALS OF PANAMA GOLDMAN IO7 



Here, also, well-trodden paths, radiating from their holes off through 

 the vegetation, were noted. The same local area is inhabited by 

 Zygodontomys cherriei ventriosus. Both species avoid the heavy 

 forest. Many cleared spaces where they were undoubtedly abundant 

 have been inundated by the recent elevation of the level of Gatun 

 Lake. 



Specimens examined : Boqueron, 6 1 ; Bugaba, 3 " ; Gatun, 7 3 ; 

 Tabernilla, 24. 



SIGMODON AUSTERULUS Bangs 



Chiriqui Cotton Rat 



Sigmodon austerulus Bangs, Bull. Mus. Comp. Zool., Vol. 39, No. 2, p. 32, 

 April, 1902. Type from Volcan de Chiriqui, Chiriqui, Panama (altitude 

 10,000 feet). 



The type, still unique, of Sigmodon austerulus was obtained by 

 W. W. Brown, Jr., near the summit of the Volcan de Chiriqui. 



The animal is well described as " about the size of S. boruca; tail 

 longer; pelage much more hispid; colors all much paler; skull 

 similar." Quoted further the author says : " The one example from 

 the top of the Volcan de Chiriqui, differs from S. borucce of the 

 adjacent low lands not only in having much more hispid pelage, a 

 much paler coloration throughout, but also a longer tail. 



" In the forest belt of the Volcan, where Mr. Brown did much 

 trapping, he did not find Sigmodon, and for that reason I give full 

 specific rank to the form of the summit of the Volcan de Chiriqui. 

 It has been my experience that Sigmodons love open fields, savan- 

 nahs, brushy places, and waste land, and avoid the dense forest." 



Specimens examined: Volcan de Chiriqui, 1 2 (type). 



Genus RHEOMYS Thomas. Water Mice 

 The single known species representing this genus in Panama is a 

 small, dark-colored, aquatic mouse with short glossy fur. In gen- 

 eral external appearance it suggests a musk rat in miniature. In 

 the peculiar combination of cranial characters it differs widely from 

 the other rodents of the region. 



1 Collection Amer. Mus. Nat. Hist. 



1 Collection Mus. Comp. Zool. 



* One in collection Amer. Mus. Nat. Hist. 



