v.] METAMORPHOSES OF INSECTS. 83 



sequence. I do not, however, propose to discuss the 

 question of Natural Selection, but may observe that 

 it is one thing to acknowledge that in Natural Selec- 

 tion, or the survival of the fittest, Mr. Darwin has 

 called attention to a vera causa, has pointed out 

 the true explanation of certain phenomena ; but 

 it is quite another thing to maintain that all animals 

 are descended from some primordial source. 



For my own part, I am satisfied that Natural 

 Selection is a true cause, and, whatever may be the 

 final result of our present inquiries whether ani- 

 mated nature be derived from one ancestral source, 

 or from many the publication of the Origin of 

 Species will none the less have constituted an epoch 

 in the History of Biology. But, how far the present 

 condition of living beings is due to that cause ; how 

 far, on the other hand, the action of Natural Selec- 

 tion has been modified and checked by other natural 

 laws by the unalterability of types, by atavism, &c. ; 

 how many types of life originally came into being ; 

 and whether they arose simultaneously or succes- 

 sively, these and many other similar questions 

 remain unsolved, even admitting the theory of Natural 

 Selection. All this has indeed been clearly pointed 

 out by Mr. Darwin himself, and would not need re- 

 petition but for the careless criticism by which in 

 too many cases the true question has been oDscured 

 Without, however, discussing the argument for and 

 against Mr. Darwin's conclusions, so often do we 

 meet with travesties of it like that which I have 

 just quoted, that it is well worth while to consider 

 the stages through which some group, say for in- 



G 2 



