4 AFRICAN SQUIRRELS. 



present a small fifth molar in each upper jaw. It is how- 

 ever an impossibility to bring them for this reason under 

 two heads, as it often happens that of two closely allied 

 species the one has x ^^^ ^^^ other | molars. The number 

 of molars is a very constant and thus a good characteristic 

 for distinguishing the several species. In adult specimens 

 the fii'st small upper molar does not fall out, as some 

 writers assert. The smoothness of the upper incisors can 

 however not be regarded as the characteristic of a distinct 

 group , nor does their grooved state enable us to separate 

 the species which present such peculiarities from their con- 

 geners. Of the nineteen species only two show the latter 

 characteristic, viz: Sciurus rufo-hrachiatus and getulus. 



Although many attempts have been made to divide the 

 Squirrels into distinct restricted groups , only a few ot 

 them can stand a more critical inquiry, as these sections 

 have been for the greater part based upon inconstant and 

 accidental characters and on the other hand upon inexact 

 and partly fancy ful observations. As to the African Squir- 

 rels I only admit two distinct groups , viz : the genera 

 ScTURUs and Xeuus and I believe that it will be prudent 

 to content ourselves provisionally which these two sections as 

 up to this time hardly anything is known about the habits of 

 these animals and as the skeletons and the other inner 

 parts have even not yet been studied. Prof. Peters is the 

 only author who gives some accounts of the anatomy of 

 a couple of his new African Squirrels. 



I have endeavored to bring all the African Squirrels 

 hitherto described under one or other of my species , but I do 

 not know to what species may belong Sciurus abessinicus 

 Thevenot, described in »les Voyages aux Indes Orientales , 

 1789, Chap. V. p. 34". He says »son poil est long et 

 »rude et d'un roux noiratre. Celui du ventre et des pieds 



»de devant est gris comme Ie poil du lièvre Les 



»Hollandais l'avaieut acheté d'un Abyssin Il est 



»trois fois plus grand que ceux que nous avous en France". 

 I never saw a Squirrel of a similar size ! 



Notes fro no. the I-ieydeii Miuseum, Vol. IV. 



