PROCEEDINGS, 1918 47 



Gastroidea polygoni Linn. 



During August, a large number of eggs of this beetle were 

 found on Wild Buckwheat (Polygonum convolvulus) A num- 

 ber of these were brought into the laboratory, a study of the in- 

 sect's life history and of its different stages was made, and the 

 following account prepared. 



Summary of Life History. 



The eggs were found during the first week in August, and 

 hatched very soon afterwards. The larvae feed heavily and 

 grow rapidly, attaining full growth in from 11 to 13 days, dur- 

 ing which time the insect moults twice. The larva then enters 

 the ground, forms an earthen cell and pupates, remaining in this 

 stage for from 11 to 14 days. The adult upon emerging feeds 

 upon its host plant for a few weeks and then goes into hiberna- 

 tion. Records of the insects' life history will be found in the 

 accompanying table. 



The Egg. 



The eggs are laid on the under side of the leaves of Wild 

 Buckwheat, in masses varying from twenty to thirty-five. 

 They differ from those of the two preceding species in that they 

 are distinctly separated from one another and lie on their side 

 mostly lengthwise of the leaf. 



Description. Cylindrical, widest at the middle, tapering 

 gradually to apex and base, both of which are bluntly rounded. 

 Chorion, smooth and shining. 



Color, rich, light yellow, some having a slight greenish 

 tinge on the cap, semi-transparent. 



Length, 1.13 m.m. — 1.16 m.m. Width .459 m.m. — .486 m.m. 



The Larva. 



The larva, like the two previously mentioned species, de- 

 vours its egg shell shortly after it emerges and then begins feed- 

 ing on the leaves; at first by merely eating the epidermis on the 

 under side, but later by eating out small circular holes. 



