Harly Stages of Albutina pJiereies. 403 



Tonge had already hatched and died. I therefore 

 thought I must somehow have killed my store of eggs of 

 V. optilete. They began, however, to hatch when they 

 had been laid more than fourteen days, being a full week 

 longer as eggs than the other two species, or their own 

 brothers sent to England by post. 



The larvae of V. optilete fed slowly and steadily and 

 ate Vaccinium. myrtillus as readily as V. uliginosum. 

 They all fed up to third stage and went into hibernation, 

 not one offering to feed up as an autumn specimen. The 

 young larvae do not mine like those of A. pheretes, but 

 eat out little pits, between the nervures. 



The A. pheretes feed up at considerably different rates. 

 A majority elected to hibernate in the third instar, a fair 

 number went on into the fourth instar, and I imagined 

 all these intended to feed up as autumn specimens. Most 

 of them, however, selected to hibernate, and only three 

 or four went forward; these were not very vigorous and 

 only one succeeded in reaching the pupal stage and that 

 not quite healthily. Their doing so, however, enabled me 

 to follow through the life history. 



It seems probable that neither of these three species 

 can ever produce an autumn brood naturally ; and it is 

 curious that V. optilete, the lowest level species, if there 

 be any difference, resisted all temptation to produce an 

 autumn emergence, whilst orhitulus did so readily and 

 p)lieretes very sparingly. It is necessary of course to 

 remember the very warm August during which they 

 were reared at Reigate. 



It is important to call attention to the circumstance that 

 the larva of A. p>he,retes, hibernates, preferably perhaps in 

 the third instar, but nearly as commonly in the fourth, and 

 it was one of the latter that I successfully hibernated. 

 All other larvae of " Blues " of which I have accurate 

 notes, that hibernate half grown, do so in the third instar, 

 a habit to which optilete and orhitiUus strictly conform. 



Explanation of Plates XVIII-XXXVI 



Plate XVIII shows the larva in third, fourth and fifth instars. The 

 third and fourth instars differ little except that the dark colouring 

 is more frequently distinct and even pronounced in the third instar. 

 So that the figures of fourth instar would be equally good for the third, 

 only that larvae of ditl'erent colouring have been selected, only a few 



