l']2 COLEOPTERA 



but does not take food, and in the course of a few days again moults 

 and discloses the true pupa (Fig. 140, E). As usual in Coleoptera 

 this instar lasts but a short time, and in five or six days the perfect 

 beetle appears (Fig. 140, F). It is extremely difficult to frame any 

 explanation of this complex development ; there are, it will be 

 noticed, no less than five stages interposed between the first 

 larval instar and the pupal instar, and the creature assumes in 

 the penultimate one a quasi-pupal state, to again quit it for 

 a return to a previous state. It is possible to look on the 

 triungulin and the pupal instars as special adaptations to external 

 conditions ; but it is not possible to account for the intermediate 

 instars in this way, and we must look on them as necessitated by 

 the physiological processes going on internally. Nothing, how- 

 ever, is known as to these. It may be well to mention that, 

 after describing and figuring (loc. cit.) this series of instars, Kiley 

 changed his views as to their nomenclature.^ The following 

 summary of the metamorphosis, to which we have added the two 

 nomenclatures of Eiley — the original one, when different from the 

 amended one, being given in square brackets — -may therefore be 

 useful, viz. — Egg; 1, triungulin-larva — moult; 2, Caraboid larva 

 [second larva, Caraboid stage] — moult ; 3, Scarabaeoid larva 

 [second larva, Scarabaeoid stage] — moult ; 4, Scarabaeoid larva 

 [second larva, ultimate stage] (large amount of food and much 

 growth) — -moult ; 5, coarctate larva [pseudo-pupa, or semi pupa] ; 

 6, Scolytoid larva [third larva] (active, but little or no food taken) 

 — moult ; 7, pupa — moult ; 8, perfect Insect. 



M. Fabre has succeeded in elucidating the history of Sitaris 

 humeralis, a Cantbarid that lives at the expense of bees of the 

 genus Anthojyhora." The eggs of the Sitaris are deposited in 

 the earth in close proximity to the entrances to the bees' nests, 

 about August. They are very numerous, a single female pro- 

 ducing, it is believed, upwards of 2000 eggs. In about a month 

 — towards the end of September — they hatch, producing a 

 tiny triungulin of black colour ; the larvae do not, however, 

 move away, but, without taking any food, hibernate in a heap, 

 remaining in this state till the following April or May, when 

 they become active. Although they are close to the abodes of 

 the bees they do not enter them, but seek to attach themselves 



' Amer. Nat. xvii. 1883, p. 790. 

 " For illustration of this metamorphosis, see Vol. V. p. 159 of this work. 



