444 History of the Sexual Theory. 



the processes of fertilisation in Cryptogams and in the lower 

 animals ; here is another confirmation of the fact, often 

 brought out in other ways by modern zoological and botanical 

 research, that the points of resemblance in the vegetable and 

 animal kingdoms appear most plainly, if we compare together 

 the simplest forms to be found in both ; we have in this fact a 

 plain proof also, that both kingdoms have been developed from 

 like common elements, as the theory of descent implies. With 

 respect to the true nature of fertilisation itself, which is evidently 

 a similar process in the main in animals and plants, we can 

 only say at present, that it amounts in all cases to a material 

 blending together of the contents of two cells, neither of which 

 is capable of further development by itself, while the product 

 of the combination is not only capable of such development, 

 but unites in itself the characteristics of the two parent forms 

 and transmits them to its descendants. That fertilisation is 

 not the intimate union of two bodies possessing a definite 

 form, but that the male fertilising substance at least may be a 

 simple fluid, appears to be distinctly shown by the process in 

 Phanerogams ; and we may assume, that in Cryptogams also, 

 the sexual act is not affected by the form of the fertilisation- 

 elements, though a certain shape and power of movement is 

 necessary for the conveyance of the fertilising substance to that 

 which is to be fertilised. 



