SUPERFAMILY TINEOIDEA 145 



as far as central New York and eastern Ontario. When 

 abundant the tips of the mined leaves shrivel away and the 

 trees assume the aspect of being severely frosted. From 

 some observations at Ithaca in 1912, Professor Herrick 

 estimated that a single larva may eat or injure as many as 

 a hundred different leaves after becoming active in the 

 spring. What then must have been the severity of the 

 attack on larches in Sweden in which Ivar Traegardh 

 counted as many as twenty-seven, forty-one, and even 

 seventy-four cases hibernating beside single buds! 



The moths are small and silvery grayish brown without 

 conspicuous markings. In the northeastern United States 

 they issue during late May or early June. Mating soon 

 takes place and the eggs are deposited on the leaves within 

 a week or ten days after emergence. 



The eggs are small, having about a third the diameter of 

 the leaves, but are plainly visible to the naked eye. In color 

 they are reddish brown. Their shape is that of shallow 

 inverted bowls, with a depression at the apex and twelve 

 to fourteen rather bold ridges radiating down the sides. In 

 hatching the larvae bore through the base of the egg directly 

 through the leaf cuticle into the interior, thus avoiding 

 exposure on the surface of the leaf. They begin to mine, 

 at first very slowly, and remain in this single leaf from late 

 June until September. The needles containing the larvae 

 become somewhat transparent and russetted during late 

 summer. The excrement of this period is packed into one 

 end of the mine. 



In September the larvae prepare their first cases which 

 they later use as hibernating chambers. For these they 

 either use the leaves in which they have been living during 

 the summer, cutting off the distal end and clearing out the 

 excrement, or they leave these mines and burrow into fresh 

 needles before making a case. Having cleaned the burrow 



