ON THE BEAIN IN THE EXTINCT LEMURS OF MADAGASCAE. 163 



APPENDIX. 



On the Form of the Brain in the Extinct Lemurs of Madagascar, with some Bemarks 

 on the Affinities of the Indrisinse. By G. Elliot Smith, M.A., M.B., F.B.S., 

 Professor of Anatomy, The School of Medicine, Cairo. 



Eeceived May 8, read May 28, 1907. 

 (Text-figures 63-63.) 



In this communicatioii I propose to describe the features of the cranial casts of three 

 extinct Prosimise recently found in Madagascar by Mr. H. F. Standing, who has given 

 them the names Lemur jullyi, Mesopropithecus pithecoides, and Palceopropithecus 

 maonmus, respectively. I shall also seize the opportunity of adding some notes on 

 the interpretation of the brain-casts of Nesopithecus and Megaladapis (which I have 

 described elsewhere [i, 2, and 3]) in the light of new information which the study of 

 these specimens and the histology of the brain in recent Lemurs has yielded. 



With the help of the data which two of these three new casts supply, I hope 

 to be able to demonstrate an undoubted affinity between the living Indrisinse and 

 Chiromys, and the extinct genera Mesopropithecus, Palceopropithecus, Nesopithecus, 

 and Megaladapis. 



In my former memoirs (i, 2, and 3) my chief aim was to enquire into the possibility 

 of homologising cerebral sulci in the Primates and the other mammalian orders ; and 

 for this reason I endeavoured to apply to the furrows of the Prosimian brain, the 

 Primate homologies of which are in most cases obvious, the names which it is customary 

 to employ in describing the Carnivore, Ungulate, and other mammalian types of 

 brain. How amply I was justified in this procedure everyone who is acquainted with 

 the recent histological localisation of the cerebral cortex must be aware ; but there is 

 no need to continue the use of this nomenclature in the present instance, so I shall 

 employ the common Primate terminology, which will not only eliminate contentious 

 matter but also more readily facilitate the comparisons with the Apes, which will be 

 discussed in the course of the description. 



At the outset I must express my best thanks to Dr. A. Smith Woodward, Keeper 

 of the Department of Geology in the British Museum, and Mr. Standing for the 

 opportunity of examining these casts. 



The Form of the Brain in Lemur jullyi. 



In my earlier memoir on the Prosimian brain (i) I was able to include some notes 

 (pp. 336 and 337) on the features of the brain in Lemur jullyi, based upon the 

 examination of a skull kindly lent me by Dr. Forsyth Major. The brain of that 

 specimen was 10 mm. longer and 5 mm. broader than the largest example that I had 

 obtained from a recent Lemur (of the species varius). The brain-cast with which we 



VOL. xviii. — part II. No. 14. — May, 1908. 2 



