en. xvi.] FERTILISATION OP FLOWERS 317 



studying organic phenomena in their least complicated 

 forms ; and this point of view, which, if one may use the ex- 

 pression without disrespect, had something of the amateur 

 about it, was in itself of the greatest importance. For, from 

 not being, till he took up any point, familiar with the liter- 

 ature bearing on it, his mind was absolutely free from any 

 prepossession. He was never afraid of his facts, or of fram- 

 ing any hypothesis, however startling, which seemed to ex- 

 plain them. ... In any one else such an attitude would 

 have produced much work that was crude and rash. But 

 Mr. Darwin if one may venture on language which will 

 strike no one who had conversed with him as over-strained 

 seemed by gentle persuasion to have penetrated that re- 

 serve of nature which baffles smaller men. In other words, 

 his long experience had given him a kind of instinctive in- 

 sight into the method of attack of any biological problem, 

 however unfamiliar to him, while he rigidly controlled the 

 fertility of his mind in hypothetical explanations by the no 

 less fertility of ingeniously devised experiment." 



To form any just idea of the greatness of the revolution 

 worked by my father's researches in the study of the fertili- 

 sation of flowers, it is necessary to know from what a con- 

 dition this branch of knowledge has emerged. It should 

 be remembered that it was only during the early years of 

 the present century that the idea of sex, as applied to plants, 

 became firmly established. Sachs, in his History of Botany * 

 (1875), has given some striking illustrations of the remark- 

 able slowness with which its acceptance gained ground. He 

 remarks that when we consider the experimental proofs given 

 by Camerarius (1694), and by Kolreuter (1761-66), it ap- 

 pears incredible that doubts should afterwards have been 

 raised as to the sexuality of plants. Yet he shows that such 

 doubts did actually repeatedly crop up. These adverse criti- 

 cisms rested for the most part on careless experiments, but 

 in many cases on a priori arguments. Even as late as 1820, 

 a book of this kind, which would now rank with circle 

 squaring, or flat-earth philosophy, was seriously noticed in a 

 botanical journal. A distinct conception of sex, as applied 

 to plants, had, in fact, not long emerged from the mists of 

 profitless discussion and feeble experiment, at the time when 

 my father began botany by attending Henslow's lectures at 

 Cambridge. 



* An English edition is published by the Clarendon Press, 1890. 



