78 ENTOMOLOGISK TIDSKRIFT IQII. 
On the right side of the leaf, delineated in fig. 4, such 
a gallery is to be seen; we notice that the gallery is not 
continued towards the edge, but turns backwards in irregular 
windings. 
It is obvious that this difference is caused by the fact of 
the leaf and the larve in the It instance being under natural 
conditions, in the 224 instance under abnormal ones. 
The ability of the larva to find its way straight to the 
edge of the leaf is very likely due to a kind of #oprsm, 
but I have not had an opportunity of studying which 
kind. As the leaves, when picked, were put into a woo- 
den box, one upon the other, and the larvæ thus became 
enclosed in a dark chamber, it is, however, possible that it 
was this profound change in the environments which confused 
the larvæ and made them lose their bearings, not only the 
circumstance of the leaves having been picked off. 
