4 14 History of the Sexual Theory. [BOOK HI. 



plants were at that time often regarded on insufficient grounds 

 as true seeds ; Gartner distinguished them from seeds, because 

 they are formed without fertilisation and yet are capable of 

 germination, whereas ovules become seeds capable of germina- 

 tion only under the influence of the pollen. He distinctly denied 

 the sexuality of the Cryptogams ; it was not till fifty years later 

 that strict scientific proof was substituted in this department 

 of botany for vague conjecture, and it was more in the interest 

 of true science in Gartner's day to deny sexuality in the Cryp- 

 togams altogether, than to take the stomata in Ferns with 

 Gleichen, or the indusium with Koelreuter, or the volva in 

 Mushrooms for the male organs of fertilisation. Gartner rightly 

 appealed to Koelreuter's hybrids against the defenders of the 

 theory of evolution; and to those who saw in the seed only 

 another form of vegetative bud, he said, that the bud can 

 produce a new plant without fertilisation but that the seed 

 cannot. We have already given an account in the chapters on 

 Systematic Botany of the services rendered by Gartner to the 

 knowledge of the seed in its immature and in its mature 

 condition ; as regards the process of fertilisation he adopted in 

 the main Koelreuter's view, that it is the result of the union 

 of a male and female fluid, from which the germ-corpuscle in 

 the ovule is developed by a kind of crystallisation. Konrad 

 Sprengel also fully committed himself to this view, and was 

 thereby prevented from understanding the process of fertilisa- 

 tion in Asclepiadeae. 



In KONRAD SPRENGEL * we encounter once more an observer 



1 Christian Konrad Sprengel, born 1750, was for some time Rector at 

 Spandau. There he began to occupy himself with botany, and devoted so 

 much time to it that he neglected the duties of his office, and even the 

 Sunday's sermon, and was removed from his post. He afterward lived a 

 solitary life in straitened circumstances in Berlin, being shunned by men 

 of science as a strange, eccentric person. He supported himself by giving 

 instruction in languages and in botany, using his Sundays for excursions, 

 which any one who chose could join on payment of two or three groschen. 

 He met with so little support and encouragement that he never brought out 





