55 



attacked by Apanteles glomeratus. This was not the only 

 immigration from the Continent that arrived on our shores ; 

 many observers were gladdened by the sight of numerous 

 crossbills (Loxia curvtrostra), which, as Mr. W. L. Distant 

 very kindly informs me, were seen in nearly all parts of the 

 country. Mr. Distant has called 1909 the " crossbill " year, 

 and no doubt it will, among ornithologists, long hold this 

 designation. 



Lepidopterous Evolution. 



During the last few years my attention has been drawn, 

 as far as entomology is concerned, more particularly to the 

 life-cycle, or, as we often wrongly call it, life-history, of 

 various species of Lepidoptera. I have bred from the egg, 

 and have made more or less detailed notes on the external 

 appearance and habits, as far as can be done in captivity, 

 of some of the species of what we call the lower forms of 

 Lepidoptera, as well as of some of those species which, we 

 generally consider, have reached a higher status from an 

 evolutionary point of view. In rearing Lepidoptera from the 

 egg we may obtain a fair notion of the various stages through 

 which our captives pass, of some of their habits, and of the 

 disposition even of certain individuals, but of their real life- 

 history we gain but little. That can only be approximately 

 learnt by patient study of a species in its natural surround- 

 ings, extending over many seasons. In rearing Lepidoptera 

 from the egg one is insensibly led to weigh in the mind 

 various points connected with the theory of evolution. 



The evolution of a lepidopterous insect appears far more 

 complicated than the evolution of, say, such an animal as 

 we now call a quadruped, for when once the quadruped 

 commences life on its own account — that is to say, when it 

 is born — its own structure and the conditions under which 

 it usually lives remain practically the same throughout its 

 whole life. The lepidopteron, on the other hand, may be said 

 to have four distinct phases of life — the life in the egg after 

 that has been deposited, the larval, pupal, and the imaginal 

 life. I think there is no doubt that evolution takes place in 

 all these four lives, or phases of life, independently. The 

 aim of life, the structure, and the conditions of environment 

 are different in all the four phases. The height of evolution 

 reached in one stage does not, or need not, affect any of the 

 other stages, except in so far as to make that change in the 

 germ-cells which may be necessary to the further evolution 



