498 POSITION AND AFFINITIKS OF TAllSIUS. 



stock had separatecl from the stock of Primates at the Tarsms 

 level and that all resemblances ])etween the two stocks Avere clue 

 to convergent evolution. 



In Prof. MacBrirle's opinion the points of similarity between 

 Tai-sius and Man adduced by Prof. Wood-Jones were superficial 

 peculiarities, and the assertion that these structural charac- 

 teristics were absent from Monkeys seemed to rest largely on our 

 imperfect knowledge of the anatomy of Primates, as the ad- 

 mission of Prof. Wood-Jones that some of them appeared as 

 "exceptions" in the Chimpanzee and the Gorilla amply proved. 

 Prof. Elliot Smith had righ.tly emphasised the deep and funda- 

 mental resemblances between the Higher Apes and Man, and his 

 exposition would leave no doubt in the minds of most of us that 

 tlie older view that Man was sprung fi'om a Simian stock was 

 true. 



The great interest in the question of Man's oiigin was to discover 

 the cause of his evolution, for we might rest assured that Man did 

 not evolve in response to an innate tendency lodged in a Monkey's 

 constitution, but in response to needs created by a change in the 

 environment. The Apes were arboreal animals ; and Man was, 

 anatomically, a Ground-Ape. When towards the end of the warm 

 Tertiary period, the forests began to shrink and to be replaced by 

 steppes swarming with swift-footed grazing animals, the resti'iction 

 of food on the trees and its obvious abundance in the plains led 

 to the most enterjorising Apes venturing on to the ground and 

 assembling in troops to run down their prey, and thus a beginning 

 in the evolution of Palseolithic Man the primitive hunter Avas 

 made. 



The race of squirrels, essentially tree-loving animals, had, in like 

 manner, spread into steppes aiid prairies, and given rise to shoi't- 

 tailed short-legged forms like the Prairie-Dog and the Marmot, 

 which were essentially Ground -Squirrels. 



If these considerations Avere justified, it followed that the 

 phrase '" Ai'boreal Man " Avas a contradiction in terms. 



November Ith, 1919. 



A. Smith Woodaa^ard, Esq., LL.D., F.R.S., Vice-President, 

 in the Chair. 



Ml'. F. Maiitin Duncan, F.R.M.S., F.Z.S., exhibited a series 

 of photographs showing the actinic qiiality of the light from a 

 living Fi/roplioras Beetle, and described the method he had 

 employed to obtain his records. He stated that the results 

 obtained appeared to show that photo-spectroscopically the 

 greatest intensity of light action Avas in the yellow-green region. 

 Unfortunately the single specimen at his disposal Avas already in 

 a somewhat exhausted condition on cominir into his hands, so 



