432 FERTILISATION OF FLOWERS. [1837. 



flat-earth philosophy, was seriously noticed in a botanical 

 journal. 



A distinct conception of sex as applied to plants, had 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. 



When the belief in the sexuality of plants had become 

 established as an incontrovertible piece of knowledge, a 

 weight of misconception remained, weighing down any rational 

 view of the subject. Camerarius * believed (naturally enough 

 in his day) that hermaphrodite flowers are necessarily self- 

 fertilised. He had the wit to be astonished at this, a degree 

 of intelligence which, as Sachs points out, the majority of his 

 successors did not attain to. 



The following extracts from a note-book show that this 

 point occurred to my father as early as 1837 : 



" Do not plants which have male and female organs to- 

 gether [i.e. in the same flower] yet receive influence from 

 other plants ? Does not Lyell give some argument about 

 varieties being difficult to keep [true] on account of pollen 

 from other plants ? Because this may be applied to show all 

 plants do receive intermixture." 



Sprengel,t indeed, understood that the hermaphrodite 

 structure of flowers by no means necessarily leads to self- fer- 

 tilisation. But although he discovered that in many cases 

 pollen is of necessity carried to the stigma of an other flower, 

 he did not understand that in the advantage gained by the 

 intercrossing of distinct plants lies the key to the whole ques- 

 tion. Hermann Miiller has well remarked that this " omis- 

 sion was for several generations fatal to Sprengel's work. . . 

 . . For both at the time and subsequently, botanists felt 

 above all the weakness of his theory, and they set aside, along 

 with his defective ideas, his rich store of patient and acute 

 observations and his comprehensive and accurate interpreta- 



* Sachs, ' Geschichte,' p. 419. 



f Christian Conrad Sprengel, born 1750, died 1816, 



