248 DR. 0. 1. roESTTH MAJOR ON [Mar. 19, 



the face above ; the apex of the clypeus is broadly palhd yellow 

 and is sparsely punctured and almost bare. Meson otum and 

 scutellum distinctly brassy, closely punctured ; the scutellum is 

 broadly depressed in the middle. Post-scutellum unarmed and 

 thickly covered with white pubescence. Basal area of median 

 segment bare, shining and irregularly reticulated. Wings clear 

 hyaline ; the stigma and nervures black. Legs black, thickly 

 covered with white hair ; the hinder femora are dilated, above 

 they have a rounded curve from the base to the apes ; the tibiae 

 are not much narrower than the femora and become gradually wider 

 from the base to the apex, which is straight and oblique, their upper 

 side is rounded, their lower straight ; the calcaria and spines are 

 pale. The abdomen at the base has bluish tints ; the segments are 

 ringed with white hair at the apices. 



2« On Lemur mongoz and Lemur ruhriventer. 

 By C. I. Forsyth Major, F.Z.S. 



[Received March 4, 1901.] 



(Plate XXII.O 



(Text-figures 61-70.) 



It is well known to those who have approached the subject 

 that we are not yet satisfactorily acquainted with the members of 

 the genus Lemur, and that the synonymy of the species is there- 

 fore far from being settled. 



The reasons for this state of things are also known, at least in 

 great part. Some of the species vary considerably in the color- 

 ation of their skin. In others the male is different from the female 

 in outer appearance. In others again two different species 

 resemble each other in external characters. Quite a number of 

 so-called species have been introduced without sufficient de- 

 scriptions, and, the types being lost or uncertain, it is impossible 

 exactly to know what their authors had in view. 



In menageries, different varieties of the same species, or two 

 different species, have been again and again crossed together, and 

 there is every likelihood that in more than one instance species 

 have been founded upon hybrids. 



With the exception of, perhaps, the Paris Museum, no collection 

 contains sufficient materials for our present exigencies. 



And, last not least, the species have without one single 

 exception been based upon external characters, and the skull 

 especially has been almost entirely overlooked. 



Schlegel's excellent ' Monographie des Singes' of 1876, the 

 fruit of researches extending over fifty years, is still the standard 

 work from which we have to start when studying most of the 



' For explanation of the Plate, see p. 268. 



