;34G 



PEOF. G. ELLIOT SMITH ON THE 



The Bhain in the Galagin.e. 



The lirain of Gulago Guruetti may be regarded as the simplest and most generalized 

 among the Lemiivs, if Ave except that of Tarsiiis, which exhibits a peculiar combination 

 of primitive and pithecoid features imjierfectly disguised by its strangely-distorted form. 



The features of the rliinencephalon in Galar/o resemble on the whole those of the 

 I-orisime ; but the olfactory bulb is jjlumper and the rhinal Assure is more complete than 

 it is in any other genus among the Primates. 



The brain of this species is remarkable (among those of Lemurs of a corresponding size) 

 for the paucity of sulci. Only the most stable and constant sulci are present, and these 

 in a typical and clearly defined form (tig. 15). 



Fig. 15. 



(JaJago Oarnetti. 

 Lateral aspect of the left cerebral hcmi.sphere. Xat. .size. 



The " Sylvian fissure " is constituted like that of the LorisinsB, no submerged area 

 being found between its two constituent sulci. The pseudosylvian sulcus is very 

 shallow. 



Above the upj^er end of the suprasylvian (Sylvian) furrow there is a very short latei-al 

 sulcus, which is quite straight in one brain, but slightly arched in the other. 



Ihere is a simple, straight, clean-cut orbital sulcus parallel to the anterior lateral 

 fissure. 



Fig. 16. 



spc- 



Galago Garaetli. 

 Mesial aspect of the right cerebral hcmisiilierc. Xat. size. 



In one of the two brains of Galago Garnetll there is a shallow depression far forward 

 on the hemisphere just above the orbital margin : it represents the coronal sulcus. 



It resembles the brain of Lejndolenmr in having no well-defined postsylvian sulcus ; 

 but on the left hemisphere of one specimen there is a faint depression in the situation of 

 this furrow. This we have seen to happen sometimes in Lepkloleimir. 



