346 DAR WINIA NA. 



those arrangements in Mature to secure cross-fertiliza- 

 tion in the species, either constantly or occasionally, 

 which are so general, so varied and diverse, and, we 

 may add, so exquisite and wonderful, that, once pro- 

 pounded, we see that it must be true. 1 "What else, in- 

 deed, is the meaning and use of sexual reproduction % 

 Not simply increase of numbers ; for that is otherwise 

 effectually provided for by budding propagation in 

 plants and many of the lower animals. There are 

 plants, indeed, of the lower sort (such as diatoms), in 

 which the whole multiplication takes place in this 

 way, and with great rapidity. These also have sexual 

 reproduction ; but in it two old individuals are always 

 destroyed to make a single new one ! Here propaga- 

 tion diminishes the number of individuals fifty per 

 cent. Who can suppose that such a costly process as 

 this, and that all the exquisite arrangements for cross- 

 fertilization in hermaphrodite plants, do not subserve 

 some most important purpose ? How and why the 

 union of two organisms, or generally of two very mi- 



1 Here an article would be in place, explaining the arrangements in 

 Nature for cross-fertilization, or wide-breeding, in plants, through the 

 agency, sometimes of the winds, but more commonly of insects ; the 

 more so, since the development of the principle, the appreciation of its 

 importance, and its confirmation by abundant facts, are mainly due to 

 Mr. Darwin. But our reviews and notices of his early work " On the 

 Contrivances in Nature for the Fertilization of Orchids by Means of 

 Insects," in 1862, and his various subsequent papers upon other parts 

 of this subject, are either to otechnical or too fragmentary or spe- 

 cial to be here reproduced. Indeed, a popular essay is now hardly 

 needed, since the topic has been fully presented, of late years, in the 

 current popular and scientific journals, and in common educational 

 works and text-books, so that it is in the way of becoming a part — and 

 a most inviting part — of ordinary botanical instruction. 



