1864.] 245 



genetic connection becomes, the narrower become the limits within 

 which each group is confined. The coleopterous genus Lucanus, for 

 instance, varies in length from about 2 to 1 inch, while the coleopte- 

 rous genus Trichopteryx never exceeds tj',, inch in length. Unless we 

 are satisfied with Uncle Toby's philosophy, that it has pleased God to 

 make them so, it is difficult to conceive of any possible reason, why, if 

 every species was independently created, there should not exist Lucanus 

 as small as Trklinptcryx^ and Trlchopterijx as large as Lucatms. 



There is another assumption often made by writers in regard to this 

 matter of imitative forms, which I think is equally unsupported by 

 facts. Several parasitic insects have a strong general resemblance to 

 the insects upon which they are parasitic, though in a Natural Clas- 

 sification they are widely distinct, e. g. certain species of Volucella 

 and Bonihuii. Hence it is inferred that the parasite is mistaken by 

 the insect upon which it preys for an individual of its own species. 

 (Kirby & Sp. Intr.^ Letter 21, p. 407.) But to assume this is to as- 

 sume, not only that insects are far more stupid than from long obser- 

 vation I believe them to be, but also that the senses of Annulata are 

 homologous to the senses of Vertebrata, whereas such facts as Bees 

 flying home in a straight line through the densest forests and male 

 moths flying down chimneys to reach their females, prove that some of 

 their senses at all events must be constructed on a different type. 

 There is no proof whatever that substances which seem to us exactly 

 of the same color appear to insects of the same color. The yellow hairs 

 of one insect may to them seem red and the yellow hairs of another 

 blue, just as certain human eyes are what is called " color-blind," and 

 by candle-light to most of us blue appears to be green. The Volucella 

 certainly looks like a Bomhus in our eyes, but it by no means follows 

 that it looks like a Bomhus in the many-fticetted organs, which we call 

 eyes, of the Bomhus itself. Just so, the stars in the firmament appear, 

 it is said, in our eyes like the luminous dots in the Ovarian egg, but it 

 by no means follows, as Agassiz suggests, that in the eyes of an Omni- 

 present Creator, which are not subject as ours are to the laws of per- 

 spective, the stars in the firmament have such an appearance, and 

 therefore that " the thoughts which have been embodied in the uni- 

 verse are recalled within the little egg." {Methods of Study, p. 288.) 

 Of the whole number of parasitic insects certainly not one in a hundred 



