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gradual evolution of all forms of animal and vegetable life from a 

 few original germs, which theory was coming more and more into 

 general acceptance. The second wasthe theory of Natural Selection, 

 by which it was attempted to account for such evolution ; and against 

 this, though widely embraced at first, a strong reaction had set in 

 of late. It explained much, but it was quite inadequate to explain 

 everything. There was a large number of facts upon which it threw 

 no light Thus it was unable to initiate variation ; it only availed 

 itself of slight variations which already existed, and which if in any 

 way serviceable to the possessor it seized upon and further developed. 

 How variation originates in the first instance Darwin himself allows 

 that we are profoundly ignorant. Mr. Jenyns thought that we 

 could not go beyond the fact that no two living individuals were 

 exactly the same in themselves or in their surroundings, and in all 

 cases in which there were two parents, the progeny would be more 

 or less diiferent from either,— leading in many cases to a still greater 

 divergency of character as other generations succeeded. Natural 

 Selection, secondly, did not sufficiently explain cases of mimicry ; 

 many remarkable instances of this mimicry had been observed by 

 Messrs. Wallace and Bates, in which insects of one family per- 

 sonated those of another for the sake of greater security against 

 their enemies, and which possibly might have been brought about 

 by this agency, but it would not serve to explain such cases as the 

 mimicking of insects by plants, that of the fly and bee-orchis for 

 instance, where one might suppose that the strong resemblance to 

 such insects was for the purpose of attracting them to the flowers, 

 their agency being necessary for the fertilisation of the pollen; 

 •whereas, so far from this being the case, the bee-orchis is one of the 

 few species of orchids" specially modified toeifect self-fertilisation," 

 and Mr. Darwin tells us he has " never seen an insect visit these 

 flowers." Thirdly, there was great difficulty in explaining by 

 Natural Selection alone the extreme discrepancy in form and struc- 

 ture between the sexes in the case of many of the lower animals ; 

 the Psyckidoe among Lepidopterous insects were instanced, the 

 Stylopidai among Hymenoptera ; also among the Cephalopodous 

 moUusca, the extraordinary case of the Argonaut was alluded to, in 

 which the modified arms of the male, acting as the male organ, 



