:80.] 155 



THE LIFE-HISTORY OF GRAPHOLITHA NIGRICANA. 

 BY JOHN H. WOOD, M.B. 



The occurrence of this insect in England has been already re- 

 corded in this Magazine (Vol. xiv, p. 241) from a single specimen taken 

 here in the summer of 1875 or 76. As, however, it had been repeatedly 

 looked for since without success, I was beginning to fear it was an 

 accidental introduction that had failed to established itself, when, on 

 July 17th, 1879, I beat a specimen in fine order out of a group of 

 silver-fir (Abies picea). Two days later I found the little moths 

 flying in the early afternoon round these same fir trees. They flew 

 rather high, but gusts of wind occasionally brought them within reach 

 of the net, and I secured nearly twenty specimens, and then desisted 

 from fear of working the species too hard. At the end of the month 

 though much occupied with other matters, I made an effort to visit 

 the locality once more, with the hope of getting, if possible, a gravid 

 female. On this occasion no moths were to be seen flying round the 

 trees, but I beat out of the lower branches two worn individuals. 

 These were placed in a bottle with a sprig of picea : one of them died 

 very shortly, but the other lived a week, and laid seven or eight ova. 

 These, with the exception of one or two that were laid on the cork of 

 the bottle, were deposited singly on the needles. They were large, 

 round, full, and very conspicuous for the ova of so small a moth, of a 

 dirty-white colour, which afterwards became reddish, this change, 

 being seen under a lens, to be due to the development of an irregular 

 band of that colour round the base. Early in September, the larvae 

 appeared — little yellow fellows with black heads. They were placed 

 on fresh sprigs of the silken fir, but nothing more was seen of them, 

 nor could any trace of their workings be afterwards found in leaf or 

 bud, though carefully looked for. Still, I had little doubt from the 

 evident liking the moths had for this fir, that it was the proper food, 

 and that there would probably be little difficulty when spring came 

 round of again taking the matter up. On the 15th of February, the 

 attempt was made, and successfully. I found the larva3 feeding in the 

 buds, indicating their whereabouts by the covering of silk spun over 

 the spot at which they had entered. The terminal buds of the side 

 shoots were those chiefly attacked. These are usually arranged in 

 sets of three, and the larvae eat them out one after the other, con- 

 verting them into a common cavity. At this date the larvae was still 

 very small, brown, and with black head and plates. Towards the 

 middle of Aprir they became full-fed, when they came out of the buds 



