832 



the chrysalis state. When we consider, however, 

 that many species of insects are active in the pupa 

 state, and that on their exclusion therefrom they 

 have acquired their full size, and are fitted for the re- 

 production of their species, we must admit that the 

 former view of the subject is bcarcely maintainable ; 

 ami that the larva fctate, which is especially that in 

 which the digestive system predominates, and the 

 greatest supply of food is taken, is more strictly ana- 

 logous to the period of infancy of the higher animals. 



We are now to examine, 



Section 2. The peculiarities exhibited by insects in 

 their passage to the perfect state. Perhaps none of 

 the phenomena of natural history have attracted a 

 greater share of the attention of mankind in all ages, 

 than those exhibited by insects in their passage to the 

 perfect state. It is perfectly consistent with that 

 innate propensity of the human mind towards the 

 marvellous, that the change of a caterpillar into a but- 

 terfly should have been considered by the ancients as 

 a true metamorphosis, in no manner reconcilcable 

 with the ordinary process of nature. If this were 

 indeed the case in the darker days of zoological 

 knowledge, when the true nature of these changes 

 was not understood, it is equally certain that the sub- 

 ject has lost none of its interest, although, owing to 

 the admirable researches of Libavius and Redi, Mal- 

 phighi and Swammerdam, Reaumur and De Geer, all 

 of the marvellous has been removed, and a series of 

 gradual developments exposed far exceeding in pecu- 

 liarity those exhibited in any of the other tribes of 

 animals. 



But it is not alone in elucidating the nature of the 

 changes, by means of which a caterpillar becomes a 

 butterfly, that the researches of these authors are 

 most valuable ; since this discovery naturally led to 

 the equally important truth that the caterpillar is pro- 

 duced from a creature which has at one period of its 

 existence resembled itself; and which, having arrived 

 at its jKirfect state, and been impregnated, has per- 

 petuated its species by the deposition of eggs, which, 

 when hatched, produce small voracious "animals of 

 variable forms, ordinarily termed caterpillars, grubs, 

 ormaggots.and systematically larva^plural ofthe Latin 

 word larva), liable to a series of moultings, varying 

 in number. To this state in the majority of insects, 

 succeeds a quiescent period, during which the appear- 

 ance of the creature is completely altered. The in- 

 sect in this state is termed a chrysalis, or aurelia, and 

 more generally and technically a pupa (plural, pup^e). 

 After remaining in this state a certain period, the in- 

 sect again throws off its covering, and appears in its 

 perfect form. It is now termed a beetle, butterfly, 

 bee, &c., according to its kind, but technically and 

 generally the term imago is applied, to designate the 

 adult state of all insects. These terms, larva, pupa 

 and imago, were employed by Linnaeus, whose no- 

 menclature was often fanciful, although generally 

 applicable ; the first, in allusion to the laroated, or 

 nuukcd appearance of the insect whilst a larva ; the 

 second, from the resemblance of the insect, during the 

 pupa state, to the mummy-like appearance of chiU 

 ^ren wrapt up in swaddling clothes ; and the third, 

 because having laid aside its mask, and cast off its 

 waddling clothes, it is now in its perfect state, and 

 lias become a true representation or image of its 

 species. Hence the four stages of an insect's exist- 

 ence are the egg, larva, pupa, and imago. 



is true, however, that, as we have already 



ECT. . 



shown in our articles APHIDES and BLOWFLY, the 

 eggs, but very rarely, are hatched within the body 

 of the parent fly, and deposited as larvce ; and that, in 

 the Hipjwboscidce, the larva even undergoes its change 

 to the pupa state previous to being deposited by the 

 parent ; but still these insects have originated from 

 eggs ; and it is also true, that in some groups the 

 insect in the pupa state is active, and differs only 

 from the larva in having small tubercular rudiments 

 of wings upon the back (as in the orders Hcmiptera 

 and Orthoptera) ; and in the apterous individuals of 

 these orders it is next to impossible to assert whether 

 an individual be in the larva, pupa, or imago stt-.te. 

 These are, however, but exceptions to the general 

 rule, and do not warrant the opinion maintained in 

 an ingenious paper published by Mr. Newman in the 

 Entomological Magazine, to which we would refer 

 the reader ; namely, thut insects have but three 

 stages of existence, the fuital, the adolescent, and the 

 adult, inasmuch as in the majority of insects, the last 

 is preceded by a distinct but variable state, which we 

 have above noticed as that of the pupa. In like 

 manner, we see no sufficient grounds for rejecting 

 the terms larva and pupa, and employing such terms 

 as infancy and adolescence in their stead. Indeed, the 

 setting aside of words employed in a technical sense, 

 and universally understood, merely because they may 

 happen to be in a foreign tongue, or may, even in 

 their origin, have been somewhat fanciful, appears to 

 us to savour somewhat of affectation, or even some- 

 thingworse than this, when the perfectly quiescent and 

 apparently lifeless state of an insect is regarded as 

 analogous to the adolescence of the higher animals. 



Our present inqui^, therefore, resolves itself into 

 four distinct heads namely, the egg, larva, pupa, and 

 imago. 



I. Tfie Egg. We have already seen in the pre- 

 sent article, as well as in various others of our ento- 

 mological articles, that there is no ground for the 

 popular idea that any kind of insect is produced other- 

 wise than from eggs deposited by a parent. The 

 first branch of our inquiry will therefore be devoted 

 to the situation in which the eggs of insects are 

 deposited, and the extraordinary instinct exhibited 

 by the female in this operation, and which has been 

 attributed to the influence of maternal affection. As, 

 however, it happens that, in the great majority of 

 instances, the female dies immediately after deposit- 

 ing, and long previous to the hatching of, her eggs ; 

 and as, moreover, it is erroneous to attribute such 

 feelings as love or affection to animals so low in the 

 scale of existence as insects, we would refer these 

 proceedings to the operation of that indefinable 

 influence which is ordinarily termed instinct. That 

 this is a correct view of the matter, must be evident 

 from a perusal ofthe details which we have furnished 

 of the proceedings of the hive-bee and of the ants ; 

 where we have seen that insects incapable of re-pro- 

 duction (neuter?) are equally active in preparing 

 nests, &c., as the real parent. This branch, therefore, 

 of our inquiry, ought perhaps more correctly to come [ 

 into our physiological view of insects, although it can 

 hardly be said to be out of place here. 



Insects, as regards the situations in which their fggs 

 are deposited, may be divided into two classes; those 

 which, with much labour, form a residence, and lay up 

 a store of food for their progeny ; and those which 

 simply place them in situations where the young, when 

 hatched, will be certain to find a due supply of food. 



