174 LEAF-MINING INSECTS 



A Rocky Mountain species of Litharapteryx, L. abronia- 

 ella, was reported by Dyar (1903) to be a leaf -miner of mixed 

 habits: 



The larvae form variously shaped blotch mines, with a hole by 

 which frass is extruded; they also spin among the terminal leaves 

 or flower bracts with a delicate web in which the frass is contained . 

 The food plant is Alliona nyctaginea. 



An odd bit of very localized and temporary leaf-mining 

 occurs in another member of this family, Erineda aenea, as 

 reported by Miss Braun (1918) : 



The larvae feed on the spores of two species of ferns (Asplenium 

 angustifoliwn and A. acrostichoides). A web, beneath which the 

 larva feeds, is spun along the under side of the leaflet, often extend- 

 ing for three-fourths its length by the time the larva reaches 

 maturity. When young the larva mines into the sorus, eating out 

 the greater portion of the spores, and leaving the indusium hollow. 

 Later the larva becomes too large to mine, and consumes the 

 entire sorus, except the annuli of the sporangia. 



