74 



THE YOUNG NATURALIST. 



is an important element in insect 

 economy, and the appearance of a 

 species at an unusual period is often 

 important ; either an unusual period 

 of the year, or the day — as an autumn 

 species in June, or a Butterfly on the 

 wing at night ( V. Atalanta for instance). 

 A very important thing is a full list of 

 all the species that have been taken 

 within a certain area or district. It 

 matters little whether such district be 

 limited to the immediate neighbourhood 

 of the place where the collector lives, 

 or whether it embraces an entire 

 country. Its value depends on its 

 completeness, and if no previous list 

 has appeared, make one as complete as 

 you can, and as you add to it in the 

 future, send particulars of those addi- 

 tions to the former list. It is always 

 well, in lists of this class, to say a word 

 or two about the geology and botany 

 of the district. When an insect of one 

 district is known to differ in food, habits, 

 or color from the same insect in another 

 district, it should always be noted. If 

 this had been done more carefully in 

 the past, we should have understood 

 insect distribution much better than we 

 do now. 



We have often spoken about the im- 

 portance of the subject of variation. 

 All varieties ought to be recorded with- 

 out exception, and on this point we 

 would wish to make one remark, at the 

 risk of being contradicted. Varieties 

 are of two classes, those that occur with 

 some degree of regularity, generally in 

 certain places, as the var. Valezina, in 

 the New Forest; Artaxerxes, in the 



j North, &c.J and those that are excep- 

 ! tional and often unique, such as Caja, ? 

 i with wing differing on opposite sides, | 

 males with one or more wings female, 

 and such like. The remark we wish 

 1 to make is, that the first class of varie- 

 ties, are much more important than the L 

 ; second, though we know they are not f 

 '. as much prized. Those in which a f 

 | seemingly natural change is taking, or 

 | has taken place, are interesting on that 

 | very account, as showing or helping to 

 show, how what we call species have i 

 been brought about. Abnormal forms ft 

 are only monstrosities, like a kitten 

 with six legs. We have spoken above 

 i of the perfect insect only. Larvae, 

 found under any of the above conditions 

 ! are equally worth recording, and there 

 I are some special matters connected with 

 larvae also. For instance, when they 

 ' are found on a strange food plant, 

 ' it should always be noted; and also 



when this happens, whether the usual j 

 j food plant is wanting where they are J 

 j found, or is plentiful, so as to show » 

 ' whether the change has been made from \ 

 j choice or necessity. Varieties of Larva? J 

 are rare, and should always be noted, j 

 Certain species are known to have more 

 than one form, and we have little doubt, 

 more careful observation would add 

 greatly to the number. 



We have directed our remarks prin- 

 cipally to Lepidopterists, because they 

 form the larger portion of our readers, 

 but their spirit will apply equally well 

 to students in all other -branches of 

 Natural History, and are intended to 

 be applied by them also. 



