138 liVSllCTS ATTACKING WEEDS IN MINNESOTA. 



and the life liistoiA' if ])ossihle. 'Vhv I )ii)tt'ra Lepid" 'ptera, and 

 Coleoptera were j.',i\en special attention, while the ileniii)tera were 

 almost neglected. 



The sul)iect is. therefore, a \ery ct)mplex one anil mdy a 

 complete knowledge will help us to sol\e some of the dihiculties. 

 The author realizes that he has made onl_\- a beginning- : it is hoped. 

 however, that it will stimulate others tt) carry on the subject. 



CL'RLED DOCK { Kumcx cris/^ls L.) Insects. 

 The Curled Dock Leaf-miner ( f\\i:;(>iiiyia hicolcr W'eid;. 



These larvae were commonly found on June 3, making large 

 blotch mines, esjiecially in the lower lea\es. ( )ne larva pupated 

 on June 15, the adult having emerged on July 8. Two to six eggs 

 are laid on the under surface of the lea\es. 



Egg. — Length 1.1 mm. by 3 10 mm. wide. Color, dull white. 

 A polygonal scul])ture visible on the surface. ( )ne end of the egg 

 js rcnmded. while the o])posite end tapers to a point. 



Maiitiira tloridaiia Crotch? 



The lar\a < »f a small brownish llea-beetle were found mining 

 in the leaves on June Zi, but they were not common. Adults 

 emerged on Jul}- 4. 



WILD r.L'CKWHEAT I Polygonum coiivolrithis \..i Insects. 

 The Knotweed Leaf Beetle (Gasiroidca f'olyi^oiii Linny. 



These l)eetles were first ol)served on the plants oxipositing on 

 August 4. The yellowish eggs are laid in a mass on the under side 

 of the leaves, each one being about one mm. in length. The eggs 

 were hatching on August 8. the young larvae devouring the leaves 

 greedily. The females have the abdomen very much swollen, are 

 about 4' 2 mm. in length, with head and elytra green, while the 

 thorax and legs are reddish. 



Since the weed on which it was found belongs to the buckwheat 

 family, an attempt was made to rear them on the cultivated buck- 

 wheat. The adults, as well as the larvae, eat the leaves, and depos- 

 ited eggs. Altho this species is not a pest of buckwheat, it is 

 possible that it might be. However, there is little chance of serious 

 injury because the buckwheat is stich a thrifty grower. 



