774 MONOGRAPHS OF NORTH A.MBRIOAN RODENTIA. 



"Les parties infc'rieures du corps et les parties internes des membres, 

 ainsi que le tour de la bouclie, sont d'ltn gris clair legerement teinte de jaune. 

 Les poils des cotes iln ventre ont les deux memes couleurs que les poils du 

 dos, niais sont beaucoup plus courts. Les poils plus courts qui couvrent le 

 milieu du ventre et de la poitrine, presentent aussi les deux meraes couleurs; 

 raais avec cette difference que le blanc ou le fauve occupe la plus grande partie 

 de leur 6* tend us. 



"La queue, ronde et non distiquc, est, sauf sa base dont la couleur a ele* 

 plus haut indiquee, d'un gris blanchatre, les poils t'tant noirs dans leur pre- 

 miere portion, puis blanc vers leur extre'mite'. De plus, parmi eux, sont 

 entremelds quelques poils entierement blancs." 



In comparing this species with his S. " aureogaster" (jrzleucops, necaureo- 

 gaster F. Cuv.), described and figured in the same work, he dwells particularly 

 upon the differences in dentition that exist between them, not only in respect 

 to the form of the teeth, but in respect to the presence in S. nebouxi of only 

 a single upper premolar instead of two. 



This species, here given provisionally, seems quite different from any 

 other hitherto described ; it may, however, be merely a gray phase of some 

 other well-known species, possibly of Sciurus hypopyrrhus. 



2.— Sciurus dimidiatus Waterh. 



Sciurus dimidiatus Waterhousk, Proc. Zool. Soc. 1840, 21. ■ 



Macroxus dimidiatus Ghay, Ann. and Mag. Nat. Hint. 3d ser. xx, 1867, 434. 



This species, described originally by Waterhouse as probably South 

 American, I am unable to identify with any American species. It is thus far 

 known only from Waterhouse's original specimen from an unknown locality. 

 As Dr. Gray has suggested, it is more likely of African origin. Mr. Water- 

 house's description is as follows: — 



" Sciurus dimidiatus. Sci. supra griseus fulvo lavatus, subtus flavus ; 

 capite, corpore ad latera pedibusque rufuscentibus ; cauda fere corporis longi- 

 tudinem ;equante, induta pilis nigris, flavis atque fulvis commixtis. 



nnc. tin. 



"Longitude ab apice costri ad cauUee basin - 10 



" cauda:, feift 7 



" ab apico rostri ad basin auris 1 11 



" tarsi diijitorumquc 2 3 



" auris 8 



"Hab. South America? 



"This curiously-colored species of Squirrel was purchased at a sale, and 



