318 BOTANY. [ch. xvi. 



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 (natu- 

 rally enough in his day) that hermaphrodite f 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,J indeed, understood that the hermaphrodite 

 structure of flowers by no means necessarily leads to self- 

 fertilisation. But although he discovered that in many cases 

 pollen is of necessity carried to the stigma of another jioiuer^ 

 he did not understand that in the advantage gained by the 

 intercrossing of distinct plants lies the key to the whole 

 question. Hermann Miiller* has well remarked that this 

 " omission was for several generations fatal to Sprengel's 

 work. . . . For both at the time and subsequently, bota- 

 nists felt above all the weakness of his theory, and they set 

 aside, along with his defective ideas, the rich store of his 

 patient and acute observations and his comprehensive and 

 accurate interpretations." It remained for my father to 

 convince the world that the meaning hidden in the structure 

 of flowers was to be found by seeking light in the same 

 direction in which Sprengel, seventy years before, had 

 laboured. Robert Brown was the connecting link between 

 them, for it was at his recommendation that my father in 

 1841 read Sprengel's now celebrated Secret of Nature Dis- 

 played. || 



The book impressed him as being " full of truth," al- 



* Sachs, GeschicMe d. Botanik, p. 419. 



t That is to say, flowers possessing both stamens, or male organs, and pis- 

 tils or female organs. 



X Christian Conrad Sprengel, horn 1750, died 1816. 



# Fertilisation of Flowers (Eng. Trans.) 1883, p. 3. 



|| Das entdechte Geheimniss der Natur im Baue mid in der Befruchtung 

 der Blumen. Berlin, 1793. 



