250 



LEAF-MINING INSECTS 



A few common species with vary characteristic mines 

 have been selected to illustrate something of the range of 

 the habits of this genus. 



The syringa or mock orange leaf -miner (Agromyza melam- 

 pyga Loew can be determined by its mine and host plant. 

 The^eggs are deposited under the upper epidermis usually 

 some distance from the edge of the leaf. The larva makes at 

 first a relatively long linear mine. Later the mine expands 



Fig. 76. Mine of Agromyza melampyga on syringa. 



into a small blotch about three quarters of an inch or an inch 

 long and about half as wide. The frass is laid down in two 

 broken lines, one on each side of the mine. In the blotch 

 portion of the mine the frass tends to become somewhat 

 scattered although the double line of frass can be followed. 

 These mines are not at all visible from the lower side of'the 

 leaf. They are pale green in color or even whitish. When 

 mature the larva cuts a slit usually in the upper epidermis 

 and escapes form its puparium. 



