Ciur. XIX. 
LAW OF BATTLE. 
325 
jaws and teeth less and less. The jaws, together with 
their muscles, would then have become reduced through 
disuse, as would the teeth through the not well under- 
stood principles of correlation and the economy of 
growth ; for ive everywhere see that parts which are 
no longer of service arc reduced in size. By such steps 
the original inequality between the jaws and teeth in 
the two sexes of mankind would ultimately have been 
quite obliterated. The case is almost parallel with 
that of many male Buminants, in which the canine 
teeth have been reduced to mere rudiments, or have 
disappeared, apparently in consequence of the develop- 
ment of horns. As the prodigious difference between 
the skulls of the two sexes in the Gorilla and Orang, 
stands in close relation with the development of the 
immense canine teeth in the males, we may infer that 
the reduction of the jaws and teeth in the early male 
progenitors of man led to a most striking and favourable 
change in his appearance. 
There can be little doubt that the greater size and 
strength of man, in comparison with woman, together 
with his broader shoulders, more developed muscles, 
rugged outline of body, his greater courage and pug- 
nacity, are all due in chief part to inheritance from 
some early male progenitor, who, like the existing 
anthropoid apes, -was thus characterised. These cha- 
racters will, however, have been preserved or even 
augmented during the long ages whilst man was still 
in a barbarous condition, by the strongest and boldest 
men having succeeded best in tlie general struggle for 
life, as well as in securing wives, and thus having left a 
large number of offspring. It is not probable that the 
greater strength of man was primarily acquired through 
the inherited effects of his having worked harder than 
Woman for his own subsistence and that of his family ; 
