46 



Dr. C. I. Forsyth Major. 



and that when a dielectric like resin is interposed in its path, some 

 of the characteristics of the form into which the electrified air has 

 been thrown are transferred to the resin surface as an electric charge, 

 generating the stresses and other inductive effects which result in 

 the dust and stress figures. 



Experiments corresponding to those described made in an atmo- 

 sphere of carbonic acid gas at normal atmospheric pressure, and in 

 air at pressures lower than the normal, show that the character of 

 the figure imprinted on a dielectric in receiving an electric charge 

 through a gaseous medium is largely dependent on the density of the 

 atmosphere conveying the charge ; greater density tending to con- 

 centration of the figure and attenuation to diffuseness. With an air 

 pressure supporting 85 mm. of mercury, the other conditions being 

 such as would have given at normal pressure a characteristic + star 

 figure, there was diffuse electrification of the resin surface, but there 

 were no rays. 



*' On the Brains of two Sub-Fossil Malagasy Lemuroids." By 

 C. I. Forsyth Major. Communicated by Henry Wood- 

 ward, LL.D., F.R.S., V.P.G.S. Received April 6,— Read 

 June 3, 1897. 



(Plate 5.) 



The casts here described and figured have been moulded from the 

 brain- cavities of the skulls of two sub-fossil Lemuroids from Mada- 

 gascar, the descriptions of which I have already published. For com- 

 parison with the brains of living Lemuroids the figures published by 

 P. Gervais* are the best adapted for the present purpose, since they, 

 too, are drawn from moulds of the brain cavity, and give on one 

 plate a good general idea of the variations of the Lemur brain. 



1. Globilemur Flacourti, Maj. 



The larger of the two casts was taken from the skull briefly de- 

 scribed by me at the meeting of the Zoological Society of London, 

 June 20, 1893.f 



In its general contours, as viewed from above (fig. 1), the brain of 

 this form, for which I now propose the name of Globilemur Flacourti 

 (g. n. et sp. n.), approaches most to that of the smallest members of 

 the family (Lemuridae), viz., Microcebus,% both being remarkably broad 



* Paul G-ervais, " Memoire sur les formes cerebrales propresa l'ordre des Lemurs, 

 accompagne de remarques sur la classification de ces animaux," 'Journal de 

 Zoologie,' vol. 1, 1872, pp. 5—27, PI. 2. 



f £ Zooh Soc. Proc.,' 1893, pp. 532—535. 



X P. Gervais, loc. nit, fig. 7, PI. 2. 



