REVIEWS AND NOTICES OF BOOKS. 147 



pp. xix-xx, Mr. Kirby himself shows that only two out of seven 

 groups, into which the butterflies are divided by egy characters by 

 Doherty, are semi-translucent, all the others being opatjue, and it is 

 well known that the eggs of many moths are opaque. \Vhat, too, is 

 the " kind of lid " to which Mr. Kirby refers? (2) Mr. Kirby says 

 (p. xxi.), that " true caterpillars never have more than sixteen Zw/.v." 

 Have any insects more than six legs ? (3) On p. xxix, we read : — 

 " Caterpillars are very voracious, and increase in size very rapidly ; 

 but as their tkin does vot e.rpand in proportion, it soon becomes too tii/ht. 

 Then the caterpillar moults." Is not the cause of moulting an 

 excretory function (See ^hnv^, Caudn-idi/e Nat. His., pt. v., Insects, 

 p. 1G2) ? (4) "On emerging from the pupa state, butterflies and 

 moths usually discharge a fluid /Vo»i their mouths ; and when they have 

 been unusually abundant, the phenomenon has sometimes been 

 imagined by the ignorant to be due to a rain of blood, for this fluid is 

 frequently of a red colour. When a moth emerges from the pupa this 

 jluid screes to soften the threads of the cocoon " (p. xxxiii.). Is not the 

 fluid which newdy-emerged moths and butterflies sometimes discharge, 

 evacuated from the anus ? and is not the fluid with which pupa"; soften 

 their cocoons an acid secreted by head or prothoracic glands ? How 

 can a fluid come from the mouth of a butterfly or moth, considering 

 its structure? (5) On p. xxxiii, we read that "Some moths are 

 furnished with a stromj spine under tJie win</s, which they employ to 

 saw through the silk." What is. the nature of this spine, and how is 

 it used ? On p. xxxiii, " When a butterfly or moth emerges from 



the pupa d,i first jiuid and tlwn air is forced through the 



nervures of the wings." Is a fluid ever forced through the nervures 

 ((•/(/(', Knt. Fu'c., vol. ii., p. 101) ? And again, in p. xliii, we read, 

 " The wings of insects are traversed by hollow tubes, which are 

 technically called nervures, and which sev\e,jirst as cireulatonj on/avs 

 for the fluid, which is forced through the wings on the emergence of 

 the insect from the pupa, and thus causes their expansion and 

 development; and aftenrards as air-tid)es." Surely the fluid that 

 expands the wings is forced between the upper and lower membranes 

 of the wing, and has nothing to do with the nervures at all ? (7) We 

 read again, on p. xxxiii, that " The body (of butterflies and moths) is 

 divided into three principal parts, called respectively the head, thorax, 

 and abdomen, each of which is connected with the next by a narrow 

 pedicel.'" Has the writer ever observed these pedicels between the 

 head, thorax and abdomen of Sphin.e convolindi, Xotodouta ziczac, 

 (J-eometra papiliunaria, Noctua rubi, Hi/pena proboscidalis, et cetera ? 

 (8) On p. xxxiv., we also read " Between the eyes are placed the ocelli, 

 or single eyes, on the summit of the head. In moths, there are always 

 two, when they are present at all, but in butterflies, and many genera 

 of moths, they are entirely absent. Their presence or absence forms a 

 generic character of importance among the moths." Have moths 

 really these ocelli ? Will Mr. Kirby give your readers a list of those 

 that have ? (9) " The long net used by the old collectors for catching 

 the Purple Emperors (a net on a pole tn-enty or tldrtij feet Ion;/) is now 

 rarely used" (p. 1.). Has Mr. Kirby ever looked at a stick thirty feet 

 long, and attempted to work out the improbability of its use at any 

 time? (10) " Insects pinned in the field are put into simiW iroode it 

 boxes lined with cork, and carried in the pocket." Who does this? 



