132 [June, 



quite assimilate to the dark wing disc. In several specimens both of pale and dai-k, 

 there is a tendency to a dark line along the base of the fringes of the hind-wing, 

 but in only two (one of each) is it at all marked. 



Melanism. 



How can we explain the very large proportion of dark specimens 

 amongst my bred H.. hyerana ? At first I thought that dark speci- 

 mens were unknown (one only, taken last year [1903] at Gibraltar), 

 because there were really very few specimens in collections, and this 

 is no doubt an element in the case. But then Milliere bred nearly 

 50 moths without one dark one. Milliere took his cocoons to Lyons, 

 where the climate is no doubt much hotter in summer than here, and 

 more like that of Hyeres, and so we may suppose that a cooler 

 temperature during summer may account for the difference. The 

 summer climate of Geneva, however, cannot be very different from 

 that of Lyons, and M. Bourgeois bred dark specimens there. 

 Gibraltar also is not quite British in climate. Again, we do not know 

 precisely how successful liyerana may be when at home in hiding 

 for aestivation deeply amongst stones and rubbish out of the heat. I 

 think after speculating on all possible explanations there will remain 

 an unexplained margin, only to be set down to a change in the 

 constitution of the species, by which a melanic phase has arisen, as it 

 has done in so many species in England and elsewhere. 



I hope that Mr. Powell will succeeed in throwing more light on 

 this question in the coming season. 



{To he continued). 



LIFE-HISTORY OF, AND NOTES ON, LEUCANIA FAVICOLOR, 



Barrett. 



By Paymaster-in-Chief GERVASE F. MATHEW, R.N., P.L.S., F.E.S. 

 {Concluded from fage 108). 



The young laroce when removed from beneath the flakes of wood, where they 

 lie close together side by side, at once retire to any crack available. Owing to this 

 habit I found it difficult to make a thorough examination of tlie living larvae until 

 they were well grown in the 1st skin. When freshly hatched they were pale 

 coloured, somewhat flattened dorsally, and tapering slightly from head to anus. 

 The head, which is carried horizontally, is pale brown. The scutellar plate large 

 and distinct, hairs of medium length with fairly conspicuous chitinous tubercles at 

 the base. The skin appears much wrinkled and bears a sparse coat of small 

 spicules. The larva drops on a tliread and loops but very sligiitly in crawling. 



July 2\st, 1903. — Ova of L. fallens received from Rev. C. R. N. Burrows who 

 very kindly forwarded me a large batch for comparison with favicolor. Three or 



