ENTOMOLOGY. 235 



specific difference between some of the species in the larva state, for there is 

 no appreciable or permanent distinction in the perfect insect, was occasioned 

 by difference of food; that is, a larva mining birch, might present a totally 

 different aspect to one mining hazel. Upon this Mr. Westwood has been 

 charged with holding the views of the transcendental or development school. 

 Surely there never was a more absurd charge made than this. Without 

 entering into the question of development, or maintaining for a moment views 

 which I believe have no philosophical basis, I may remark in passing, that 

 such a charge, so made, is a distinct proof that the principles of the school 

 thus impugned, have not been understood in this discussion. Now with regard 

 to the question at issue. Will Mr. Stainton, or any other person who has 

 professed to study species, or who may have observed that the habits of those 

 larvae are different, be kind enough to lay down in clear and unmistakeable 

 language, what are the differences of structure or habit upon which the 

 determinations of these species are effected. It will not do to tell us that 

 they are different in colour, because this is clearly to be accounted for in 

 the different colouring properties of leaves; for assuming that Chlorophylle is 

 alike in chemical composition and colour in different plants, provided its specific 

 gravity is the same, no one will doubt that its colouring properties vary in 

 leaves of different plants. Thus supposing it were more inspissated in a given 

 quantity of beech leaf than in the same quantity of hazel, the colouring 

 powers would be greater in the former than the latter. A. fortiori. — This 

 would be still stronger if in addition the parenchyma of the plant were more 

 condensed, and this is exactly the condition which obtains between the beech 

 and the hazel leaf. It appears manifestly absurd to suppose that if the larva 

 found it more easy to mine the upper than the under part of the leaf, or to 

 make a blotch rather than mine at all, it were to be constituted a different 

 species. I hope Mr. Westwood and others equally capable, will make a stand 

 against this modern system of making species from unimportant data. As 

 Mr. Westwood justly observed, were there any organic difference either in 

 the larva or imago, there would be good grounds, and not otherwise, for 

 constituting these insects in all essential particulars so exactly the same, into 

 different species. I also hope that they will not be induced to give way by 

 the disingenuous mode of argument, which assumes that men anxious for the 

 real progress of science, must necessarily maintain the manifest absurdity that 

 "the difference of habit was the cause of the modification of the species." — 

 Ed. 



On so-called Showers of Insects. — The English people are not alone in 

 their credulity about what are called "showers of insects or frogs." The 

 readers of the "Gardeners' Chronicle" may remember some years ago, that 

 one of the gardeners at Osborne published an account of what he called a 

 shower of snails, and he was very angry with the writer of this notice, who 

 presumed to account for the phenomenon upon grounds purely natural. The 

 good people of Warsaw have had their shower this year, much to their wonder 

 and surprise. Professor Waga has, however, in an excellent though somewhat 

 long article in the "Eevue de Zoologie," for June, also accounted for their 



