154 W. J. MOENKHAUS 
difficult to develop a strain with a female ratio much lower than 
the normal or even one in which the sexes are equal in number. 
12. Sex-ratio is one of the qualities that is, like color, an inher- 
ent characteristic of this creature, strongly transmissible and 
amenable to the process of selection. 
13. The female is almost wholly responsible in the transmis- 
sion of the sex-ratio. For, if females from a strain possessing a 
high female ratio be mated with males from a strain possessing a 
low female ratio or vice versa, the offspring will show a sex-ratio 
which is wholly or very near that of the strains from which the 
females were taken. 
14. Sex is probably very little, if at all, influenced at fertiliza- 
tion in this species, but is probably determined much earlier and 
by the female, but there seems no reason why this may not be 
influenced by various factors and in some species at fertilization. 
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