268 SECRETS OF ANIMAL LIFE 



Mr. Bonhote is not much concerned with the 

 question of the possible transmission of individually 

 acquired bodily modifications due to peculiarities 

 of, or changes in, function and environment; his 

 central idea, is that the physiological state of the 

 parent, when functioning as a parent, may influence 

 the offspring. There is abundant experimental 

 evidence to show that a slight change in the chemical 

 and physical medium of the germ-cells and the 

 early embryonic stages may have a profound effect 

 on the development. To a degree previously 

 unsuspected, appropriate liberating stimuli are 

 required to release the primordia of the various 

 organs and qualities. And there are inhibitors as 

 well as liberators. Add a drop from one philter 

 and the embryo will be blind, from another and it 

 will have no food-canal. It must be remembered, 

 too, that much depends on the tempo of develop- 

 ment, and that great changes may be brought about 

 by accelerating here and slowing there. In this 

 connection our author might have found, had he 

 known, some vindication of the emphasis which he 

 puts on " the rate of metabolism." 



To make Mr. Bonhote's point quite clear, we 

 must emphasize the fact that he is not merely con- 

 cerned with the conclusion that nurture counts for 

 much in the development or expression of the indi- 

 vidual's hereditary nature; his suggestion is that 

 nurture goes farther back. There is no doubt that 

 appropriate food and warmth and moisture and the 

 like may conspire to heighten the vigor of the parent 



