1()2 Ullcu — Some IntcrrdatLOUs of Pldnls and In^cdx. 



natural selection, of all forms departing from it. The second is 

 merely coincident, not essential, 1)ut nevertheless along lines 

 that are of secondary advantage. The third is purely fortuitous, 

 affects superficial features in the main, is unessential (a conse- 

 ([uence of the inherent tendency of all things to vary), and takes 

 })lace along all lines and in all directions where there is no coun- 

 teracting resistance. 



Now, when it comes to the l)earing which the history of these 

 little moths has upon some of the larger questions that are now 

 concerning naturalists (for instance, the transmission ofac(juired 

 characters, or the origin, development, and nature of the intel- 

 ligence displayed hy the lower animals), Ijroad liekls of interest- 

 ing oi)inion and conclusion open u]) Ijefore us — fields that cannot 

 possibly he explored without trencliing too much upon your 

 time. I will close, therefore, with a few summary expressions of 

 individual opinion, without attempting to elaborate the reasons 

 in detail, and with the object of eliciting further discussion, which 

 is one of the oljjects of the paper. My first conviction is that 

 insect life and development give no countenance to the Weiss- 

 mann school, which denies the transmission of functionally ac- 

 (juired characters, but that, on the contrary, they furnish the 

 strongest refutation of the views urged by Weissman and liis 

 followers. The little moths of which I have been s})eaking, 

 and indeed the great majority of insects — all, in fact, except 

 the truly social species — perform their humble })arts in the 

 economy of nature without teaching or example, for they are, 

 for the most part, born or])hans, and without relatives having 

 experience to communicate. The progeny of each year begins 

 its independent cycle anew. Yet every individual performs more 

 or less perfectl}' its allotted part, as did its ancestors for genera- 

 tion after generation. The correct view of the matter, and one 

 which completely refutes the more common idea of the fixity of 

 instinct, is that a certain number of individuals are, in point of 

 fiict, constantly departing from the lines of action and variation 

 most useful to the species, and that these are the individuals 

 which fail to perpetuate their kind and become eliminated 

 through the general law of natural selection. 



Whether these actions l)e purely unconscious and automatic 

 or more or less intelligent ■^and conscious does not alter the 

 fact that they are necessarily inherited. The habits and (qual- 

 ities that have been acquired by the individuals of each genera- 

 tion could have become fixed in no other way than through 



