42 STORRS AGRICULTURAL EXPERIMENT STATION 
The mines are sometimes so numerous that as they increase 
in size they run together and form one large blotch covering 
the greater part of the leaf (Fig. 5). From such a leaf were 
taken 68 full grown larvae (Fig,6), indicating that originally 
there were as many distinct mines. As the epidermis of the 
‘upper surface of the leaf ‘dies it loses its elasticity, and a curl- 
ing of the leaf inward is the result (Figs. 7 and 8). The 
leaves at this stage cease to perform their functions and soon 
drop. The higher branches of the tree are usually more seri- 
ousely affected and lose their foliage first (Fig. 9 and frontis- 
piece). This loss of foliage results in premature, undersized 
fruit. By checking its vegetative activity the vitality of the 
tree will also be more or less reduced. With regard to the ex- 
tent of injury in Vermont, Professor Stuart has to say: ‘The 
injury to the infested trees in the Station orchard was quite 

Fic. 5—A very badly infested leaf. The mines have ‘“‘run together” 
forming one large blotch covering the greater part of the leaf 
(slightly reduced). 
