GENERAL 



27 



exposing itself. All the feeding is done from the holes up- 

 ward, and full depth blotch mines are formed. 6 



The only alteration of such a habit that would be necessary 

 to make a confirmed leaf-miner would be the abandonment 

 of the bag. 



The leaf-sewer of the hog-peanut, Stilbosis tesquella, 

 manages the matter a little differently. It draws one 



Fig. 14. Diagrams of the mining operations of the midge Chironomus 

 braseniae. (After Leathers.) A, a leaf of watershield showing the tor- 

 tuous mines in the upper surface; B, a bit from the forward end of one of 

 these mines showing at c the pellets of frass held together with silk, that 

 form the roof of the mine, lying between the elevated side strips d, of 

 partially dissevered epidermis, and extending forward in a sort of porch 

 upheld by a few silken stay lines, /. 



leaflet flat upon another and sews the two together with 

 stitches of white silk placed about an eighth of an inch apart 

 all about the edges where in contact. For further security 

 it adds a few central stitches joining the stronger veins. 



8 See further in this connection the accounts of Recurvaria piceaella, 

 p. 165, and Argyresthia annetella, p. 171. 



