March, 1889.] 217 



NOTES ON THE LAKV.E OF SOME TORTRICES, COMMONLY 

 BRED FROM THE GALLS OF CTNIPS KOLLARI, &c. 



BY JOHN H. WOOD, M.B. 



By collecting the galls of Cynips Kollari in the winter, various 

 small moths, as is well known, may be bred from them in some numbers, 

 chief among which are certain Tortrices. There is good reason to 

 believe that most if not all of these insects enter the galls merely for 

 the purpose of spinning up, and are not, in a true sense, inquilines, for 

 not only do we find that it is the old dry galls that are productive, 

 while the more recent ones are barren, but also that all attempts to 

 discover the larva? actually feeding in them fail — at least, such has 

 been my own experience, and that of others, I believe, has not been 

 dissimilar. That the galls do not furnish board as well as lodging is, 

 at first sight, unexpected, because other kinds of oak-galls, as we shall 

 see, are the common food of several of these insects. But the reason 

 is not far to seek. In the woody rind of this gall lies an obstacle 

 which the jaws of the young larvae just out of the egg are unable to 

 overcome, while at the same time its smooth and globular surface offers 

 no facilities for concealment — a matter of almost as much importance 

 to the generality of larvae as food itself. If then the insects do not 

 feed in the galls, where do they? A question I now propose to answer, 

 so far as it concerns Coccyx splendidulana, Coccyx argyrana, Heusimene 

 jimoriana, and JSphippiphora gallicolana (obscurana) . 



Coccyx splendidulana.— This is a common insect in the woods of 

 Herefordshire, and its larva is to be found on the oak bushes, feeding 

 between the leaves, from the end of June to the end of July. Even 

 at this date, when the collecting of Micro-larvae is not the most 

 profitable of occupations, the oak keeps fairly rich in species ; but to 

 find them, we must pass by the rolled and folded leaves, and look 

 instead for leaves spun flat together by their surfaces. In the spring, 

 when these organs were tender and lent themselves readily to manipu- 

 lation, the larvae rolled and twisted them just as they pleased, but now 

 that they have grown stiff and leathery, such treatment is no longer 

 possible, and the larvae have to content themselves with these simpler 

 habitations, fashioned out of two adjacent leaves ; while, for greater 

 security, some of them, and C. splendidulana among the mumber, 

 spin in addition a frass-lined gallery within, the equivalent, as it were 

 of the tubular chamber of the rolled leaf. It may be taken, I believe, 

 as the rule, that larvae that live in this way never eat through the 

 whole thickness of the leaf, but leave the outer surface, whether of 



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