242 LEAF-MINING INSECTS 



The families comprising the leaf -miners of the order Dip- 

 tera are relatively few in number. Only eight of the sixty- 

 two families listed by Williston (1908) have leaf -mining 

 genera. These are given in the synopsis on page 241. 



FAMILY TIPULIDAE 



Crane flies 



In this large family there is as yet but a single known 

 leaf -mining species, Dicranomyia foliocuniculator. Swezey, 

 reared it from the leaves of Cyrtandra paludosa in the moun- 

 tains at Punaluu in the Hawaiian Islands. He states 

 (1913) that the larvae make linear mines on the leaves and 

 pupate within the mine. His figure of mine and develop- 

 mental stages, we copy herewith. 



FAMILY CECIDOMYIIDAE 



Gall midges 



This family contains, in our fauna so far as known only 

 one well-defined leaf -mining form, and another that com- 

 bines mining with gall making. These represent the two 

 genera discussed below. 



Monarthropalpus 



The boxwood leaf -miner has undoubtedly been introduced 

 from Europe. It infests ornamental hedges of its host 

 plant, damaging the appearance of the leaves. The first 

 indication of the mine appears as a small yellowish or green- 

 ish spot on the upper surface of the leaf. Opposite this, on 

 the under side of the leaf, can be seen an irregular blister, 

 caused by the maggot enlarging its mine. Later the injury 

 becomes more pronounced, and a slight elevation, with a 

 yellowish or brownish discoloration, is seen on the upper 

 surface of the leaf. The larvae pass the winter in these gall- 

 like pockets, and in the spring transform to light orange- 



