CHAPTER X 



SUPEKFAMILY YPONOMEUTOIDEA 

 YPONOMETJTIDAE 



Of this rather large family only relatively few isolated 

 species are known to be leaf-miners, and they are of a very 

 unspecialized sort, with cylindric tissue-feeding larvae that 

 pupate outside. The habits of the juniper miner, Argy- 

 resthia annetella, are summarized by Forbes (1923) as 

 follows : 



The larva mines about four leaves at the tip of a juniper twig, 

 passing through the stem from leaf to leaf, completely emptying 

 the leaves on scattering the frass. It hibernates in the mine; it 

 pupates in May in a cocoon of open meshes formed outside. 



The grass-mining Scythris, S. graminivorella, was reared 

 by Miss Braun from leaves of Hystrix. She says : 



The mine is an elongate transparent blotch with the entrance 1 

 guarded by a broad tube of silk; the larva usually makes several 

 mines. Although the species seems to prefer Hystrix as a food 

 plant, I have observed the mines on Canada blue grass, Poa com- 

 pressa. Larvae collected May 5, produced moths during the 

 first half of June. 



Most members of the typical genus Yponomeuta (the 

 ermine moths) do not mine at all; but at least one of them 

 Y. malinellus, is a leaf miner during a part of its first instar. 2 

 Parrott and Schoene (1912) have given the best account of 



1 In Hystrix, the leaf blade is twisted near the base, so that the upper 

 surface of the leaf faces downward. 



2 This species is singular in that the eggs are laid in masses on the twig 

 of apple and the larvae must seek the foliage. 



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