NO. 5 MAMMALS OF PANAMA — GOLDMAN 1 25 



time of his visit to San Miguel Island in the spring of 1900. From 

 D. darlingi of the adjacent mainland it is distinguished at once by 

 much more intense rufescent general coloration. The hind feet are 

 rusty reddish instead of silvery white. Moreover, the skull is rela- 

 tively narrower, more elongated, with smaller audital bullae. 



Regarding the habits of the species Mr. Bangs remarks : " Lon- 

 elier es labilis [ = Diplomys labilis] was abundant in San Miguel 

 Island, but was wholly arboreal, Mr. Brown catching all his specimens 

 in traps set on the branches of large trees. It appears to be diurnal, 

 and on one or two occasions Mr. Brown saw the animal proceeding 

 along the branches with a curious gliding gait, his account suggesting 

 the name I have used for the species. It is the ' Raton Marenero ' 

 of the islanders." 



Specimens examined : San Miguel Island, 14. 1 



DIPLOMYS DARLINGI (Goldman) 



Darling's Spiny Rat 



[Plate 26, figs. 1, 10] 



Isothrix darlingi Goldman, Smiths. Misc. Coll., Vol. 60, No. 2, pp. 12-13, 

 September 20, 1912. Type from Marraganti (near Real de Santa 

 Maria), on the Rio Tuyra, eastern Panama. 



This species of Diplomys was first obtained by Dr. S. T. Darling, 

 of the Sanitary Department, Isthmian Canal Commission, at Ancon, 

 Canal Zone. No member of the genus had previously been taken on 

 the Panama mainland, although an insular form described as 

 Loncheres labilis Bangs had been discovered on San Miguel Island 

 in the Bay of Panama. D. darlingi is much paler in color than 

 D. labilis, the general tone of the upperparts being ochraceous bufry 

 mixed with black, instead of the rich rufescent tint of D. labilis. The 

 feet are silvery white instead of rusty reddish as in the latter species. 

 The skull is relatively broader, the zygomata more spreading 

 anteriorly and the audital bullae are larger. It may be not very 

 unlike Diplomys caniceps (Gunther) from Medellin, Colombia, but 

 the latter seems to be somewhat different in color, with a bushy tail, 

 and the skull, as figured, differs in detail. 



Of the habits of D. darlingi little is known except that it is an 

 arboreal animal. The type specimen was seen one morning running 

 up the trunk of a tree and was shot when it paused for a moment, 

 partially hidden by the curvature of the trunk. The tree stood on 

 the low forested bank of the Rio Tuyra where that stream meets the 



1 Thirteen in collection Mus. Comp. Zool. 



