LYC^NID^ IN NORTH KENT. 221 



insects which, although they may be species, are not pure species 

 in the sense that L. icarus, P. pJilceas, and T. ruhi compared one 

 with the other are pure species. Icarus and bellargus exhibit 

 superficial points of difference ; but who shall say that during 

 the process of slight external modifications which each has 

 undergone, functional change in the internal conditions has also 

 taken place to the extent of rendering fertile union impossible 

 between these two insects. I can see nothing improbable in 

 supposing that a female of either of the species may occasionally 

 accept the amorous attentions of an importunate male of the 

 other species. 



This brings rpe to the second count in the charge I have 

 against Mr. Tutt. He makes it appear that I have suggested 

 that " icarus and bellargus copulate freely together in nature," 

 whereas I consider such a thing quite accidental, as will be seen 

 by referring to the words used, "chance crossing" (Entom. 81). 

 If any remark of mine had warranted Mr. Tutt's inference, he 

 would have been quite justified in characterising it as "more 

 than improbable." As it is, he has placed upon my words a 

 construction of his own, and to this I naturally take exception. 



With regard to atavism, I may point out that I distinctly 

 stated that I supposed the blue-black form among Mr. Sabine's 

 varieties to be an instance of reversion to certain long-lost 

 characters. Mr. Tutt appears to ignore this form altogether. 



Mr. Tutt can hardly be serious when he asks me " to point 

 out in nature anything at all compatible with (my) suggestion." 

 Any other instance of a similar character would be open to the 

 same objection as the one under discussion, and would be equally 

 improbable to Mr. Tutt. In nature we lack the most important 

 and convincing evidence — knowledge of actual parentage. In 

 forming conclusions, therefore, we have to fall back on analogy, 

 and we find many instances in the results obtained by experiments 

 with animals in domestication or confinement which afford a clue, 

 as it were, to the probable origin of such anomalous varieties as 

 those of Mr. Sabine's. 



Anyone who is interested in the subject of hybridism, will do 

 well to carefully study Chapter IX. of Darwin's ' Origin of 

 Species.' , 



12, Abbey Gardens, N.W., August 8, 1887. 



