NO. 5 MAMMALS OF PANAMA GOLDMAN 95 



the back less distinctly darkened along the median line. It seems to 

 be the most abundant murine rodent in the grassy clearings, sugar- 

 cane fields, and second growth forest of the region. It was not 

 obtained in the heavy forest and in all probability greatly increased 

 in numbers with the clearing of forest along the line of the Panama 

 Railroad. With the completion of the Gatun dam and the elevation 

 of the level of Gatun Lake much of the cleared space, including the 

 type locality, has been flooded, and the area in which these rice rats 

 and other small rodents were thriving is again restricted. Anthony 

 (1916, p. 368), who visited the Canal Zone early in 1914, reports 

 " This species was found but rarely. It was taken only at low eleva- 

 tions." He records specimens from Gatun, Real de Santa Maria and 

 Old Panama. 



Specimens examined: Empire, 4; Gatun, 12 1 ; Real de Santa 

 Maria, i 1 ; Old Panama, 1 '; Tabernilla (type locality), 15. 



ZYGODONTOMYS SEORSUS Bangs 



San Miguel Island Cane Rat 

 Zygodontomys seorsus Bangs, Amer. Nat, Vol. 35, p. 642, August, 1901. 

 Type from San Miguel Island, Panama. 



San Miguel Island is inhabited by a large, well-marked species, 

 differing from the form of Z. cherriei inhabiting the adjacent main- 

 land in much larger size, and much darker, ferruginous coloration. 



The basis of the species is a series of 68 specimens collected by 

 W. W. Brown, Jr. 



In remarks accompanying the original description, Bangs (/. c.) 

 states that " The San Miguel vesper rat is a strongly marked island 

 species, most nearly related to Z. brevicanda, of Trinidad, which it 

 precisely resembles in color and character of pelage. Its much 

 greater size, bigger foot, and different tail distinguish it, externally, 

 from the Trinidad species, and the skulls of the two can easily be 

 distinguished. 



Z. seorsus was an abundant animal in San Miguel Island, inhabit- 

 ing the dense, swampy woods, and Mr. Brown found no difficulty in 

 trapping it in numbers." 



Specimens examined : San Miguel Island, 54. 



Genus NEACOMYS Thomas. Bristly Mice 

 The members of the genus Neacomys are very small, handsome 

 mice related to Oryzomys, but with pelage composed of grooved 



1 Four in collection Amer. Mus. Nat. Hist. 



2 Collection Amer. Mus. Nat. Hist. 



