820 THE POPULAR SCIENCE MONTHLY. 



needs no further elucidation here as the principal factor in the 

 evolution in man, first of the family relation, then of the clan, 

 the tribe, and the nation. With this factor in mind, and the im- 

 mense superiority which anthropoid man must have had, when 

 brain development had once induced this fundamental community 

 of interest over the rest of brute creation, the gap between primi- 

 tive man and the higher anthropoid apes in the past, or between 

 the present lower races of man and the higher existing primates, 

 is easily explained, even if it had not been greatly exaggerated. 

 At the present time we may note and record the further inevitable 

 increase in the gap, for the lower races of man are gradually be- 

 coming extinct, and the higher apes can not long hold their own 

 or persist. 



Brooks's Hypothesis. — I have already alluded to Brooks's hy- 

 pothesis under the head of sexual differentiation, and his work 

 on heredity must be so familiar to you that his views need but a 

 passing notice. He believes that sex differentiation means funda- 

 mentally a physiological division of labor, and that the male is 

 essentially the progressive or diversifying and the female the con- 

 servative agent. As organisms gradually increased in size, as the 

 number of cells in their bodies became greater, and as the differ- 

 entiation and specialization of these cells became more and more 

 marked, one element, the male cell, became adapted for storing up 

 gemmules, and, at the same time, gradually lost its unnecessary 

 and useless power to transmit hereditary characteristics. 



The theory finds support in some of the phenomena of life, and 

 doubtless expresses a law not easily established, for which reason 

 it will not be readily accepted. It leaves entirely out of consider- 

 ation some of the forces at work which I have already indicated, 

 and in so far must be considered only a law of secondary impor- 

 tance. However much we may admit the general truth that the 

 germ-cell continues the past and the sperm-cell tends to diverge 

 from it, as a purely dynamic proposition, inducing variation for 

 natural selection to play upon, it does not in any way decrease the 

 overwhelming importance of the female in inducing, through 

 psychico-physiological influences, a needed and purposeful modi- 

 fication in the manner which I have already expounded. 



The probable character of the lang^uage of paleolithic man is the subject of 

 one of Dr. Brinton's latest studies. Taking some very primitive American lan- 

 guages as his guide, he concludes that it was more rudimentary than any language 

 known to us ; that it had no grammatical form or fixed phonetic values, but de- 

 pended largely upon gesture, tone, and stress ; that its words often had antithetic 

 meanings, which could only be determined from the accent or sign ; and that the 

 different vowel-sounds and consonantal groups conveyed specific significance, and 

 were of more import than the syllables which they formed. 



