Reports to varmis Correspondents. 37 



twigs and steins, and when so situated are extremely difficult to 

 see. 



This pest seems to affect only young stock, but I have observed 

 it on trees twelve years old. 



That hand-picking the attacked shoots does much good is evident. 

 Mr. William Bear writes on May 29th that : — " There is not so much 

 damage from pith moth as there was last year, probably because I 

 cut off and burnt every infested shoot that I saw, and I am doing so 

 again this season," 



The Apple Leaf Miner. 



{Lyonetia cJeTvl'cUa, L.). 



An ordinarily harmless insect feeding on any of our fruit trees or 

 other crops is always liable under certain conditions to increase 

 alinormally and so become destructive. This has been the case with 

 the small blister moth of the apple and pear, Cemiostoma scitella, 

 Zeller, a beautiful little Tineid which did a great deal of harm in 

 1898 in East Lothian and Cambridge.* In writing upon the life- 

 history of that pest I mentioned that " anotlier genus, Lyonetia, has 

 one species — L. dercJcella — whose larvse form long sinuous tunnels in 

 iipple and cherry trees, but do not appear ever to be abundant 

 enough to do any harm, although I have had enquiries concerning 

 tlie economy of this species." This Apple Leaf Lliner has during 

 the past season been unusually prevalent, and, in a few cases reported 

 has damaged the foliage of dwarf apple trees very considerably. 1 n 

 one instance the attack was personally investigated in Huntingdon- 

 shire and every leaf on two trees was found to be tenanted by the 

 larvffi of this minute Tineid. 



The leaves which were attacked had more or less shrivelled, and 

 many had died away in August, the trees thus receiving a serious 

 check, as the sap was still flowing freely. Tliis insect also appeared 

 in plenty in my own garden, which enabled me to keep it more or 

 less under observation. 



The presence of this leaf-miner is easily told l)y the long, sinuous 

 tunnels caused by the larva? burrowing in the leaves. As a rule !i 

 single tunnel occurs only on eacli leaf, l)uL where the damage has 

 Iteen noticed, as many as four have been present, the greater part of 

 the chlorophyll being thus destroyed. 



This moth occurs in most parts of England ; it has been es])eeially 



* J. Mir. S. E. A-iic. CoUe-e, No. 8, p. 21, 1898. 



