94 Allen Mammals of Margarita Island. 



This very distinctly characterized species appears to be nearly related 

 to Sciurits griseogena (Gray) of the neighboring coast region, rather than 

 to the 8. wstuans group. Specimens of 8. griseogena collected by Capt. 

 Robinson at San Julian, Venezuela, in July, 1900, match it closely in 

 the bright orange-rufous of the underparts, but differ very greatly in 

 the color of the dorsal surface, in which black is the predominating 

 color, due to the partial reduction of the ochraceous bands on the body 

 hairs, whereas in the Margarita squirrel the opposite change has taken 

 place, and the black has given place to the ochraceous. Moreover, the 

 entire tip of the tail is black in 8. griseogena, and bright ochraceous in S. 

 nescBus. 



.Mr. Clark obtained several of these squirrels in the woods on the 

 mountain, which is just back of El Valle, but unfortunately was able to 

 preserve only the single specimen collected near the town. This speci 

 men will be deposited with the Bangs collection in the Museum of Com 

 parative Zoology at Cambridge. 



4. Mus alexandrinus Geoff roy. Roof Rat. 



A single specimen of this rat was preserved by Mr. Clark, who states 

 that it was trapped in one of the houses at El Valle. Capt. Robinson 

 mentions "a rat (Mus)" as occurring on the island, but the species is not 

 recorded. 



5. Mus musculus Linnaeus. House Mouse. 



Both Capt. Robinson and Mr. Clark found the house mouse common 

 in the open dwellings on the island. Four specimens preserved by Mr. 

 Clark, appear to be considerably smaller than the species as found in 

 New England. Two of these, in formalin, measure about 134 mm. and 

 138 mm. in length, with tails 68 mm. and 72 mm. respectively; both 

 seem to be adult, and average 25 mm. smaller in total length than six 

 specimens from eastern Massachusetts, while the tails are also slightly 

 shorter. 



6. Loncheres sp. Spiny Rat. 

 Loncheres Robinson, Proc. U. 8. .Nat. Mus., XVIII, p. 651, 1896. 



A male specimen of a spiny rat was taken by Capt. Robinson on the 

 island, July 9, 1895. It was much injured, and in its present condition, 

 lacks the tail and part of the skin of the head. Mr. Oldfield Thomas 

 has pronounced it as being near L. punctatus. 



