834! THE STRUCTURE OF FLOWERS. 



peculiar lipped and hooded corolla with the lateral position, 

 of the flower, etc. ? We find in selecting peas and beans 

 great varieties among them, but next to none in the calyx 

 and corolla, to which the horticulturist pays no attention. 



In nature, however, we often find in flowers regularly 

 visited by insects innumerable and minutely correlated adap- 

 tations in all the whorls, which must have all varied together 

 to form such existing flowers. Now, the difficulty of their 

 doing so without some common cause, which affects them 

 all simultaneously, seems to me insuperable. 



If my theory, however, be accepted, it solves the whole 

 mystery at once, as all the changes are set up by one prime 

 cause, namely, the irritations of the insect in the case of all 

 flowers adapted to insect-fertilisation ; while the absence of 

 insects in regularly self-fertilised flowers, as well as anemo- 

 philous ones, is sufficient to account for the atrophy which 

 has affected them, the present condition of such flowers 

 having been the inevitable result. 



Hence, instead of speaking of the Origin of Species of 

 Plants by Natural Selection, I would regard the survival of 

 the fittest as first issuing from " Constitutional Selection ; " * 

 while the origin of the floral specific characters is the result 

 of the responsive power of protoplasm to external stimuli. 

 These latter ai'e infinitely various in kind and degree, as has 

 been shown in the early part of this book. The result is, that 

 while high differentiations occur in some directions, degrada- 

 tions are met with in others, sometimes seen in different parts 

 of the entire plant ; but not at all infrequently are both 

 features observable simultaneously in one and the same floral 



* Of course the chances of less competition by growing on the circum- 

 ference of the batch of seedlings, by receiving a little more light, etc., 

 aid in selecting, and sometimes may determine, as stated above, those 

 which shall survive. 



