THE CANADIAN ENTOMOLOGIST 237 



NOTES ON GALKRUCELLA NYMPHAEAE L., THE PONUTTLY 



LEAF-BEETLE (COLEOP.) 



HY HARRY B. \VEISS AND ERDMAN WEST. 

 New Brunswick, N. J. 



This species occurs throughout New Jersey on the yellow pond-lily {Nym- 

 pliaea advena Ait.) which is common along the lower Delaware River and ad- 

 jacent ditches and tide-water streams. During the seasons of 1919 and 1920, 

 it was particularly abundant at Monmouth Junction, Westville and several 

 other places in New Jersey, defacing the leaN'es and flowers and rendering them 

 ragged and unsighth'. 



Blatchleyi states that the adult probably hibernates and this appears 

 likely as adults ha\e been taken during the middle and last of May and early 

 June. The yellow eggs are deposited on the upper surfaces of the leaves in 

 clusters of 18 to 20, each "egg being stuck on end to the leaf surface and close to 

 its neighbor. MacGillivray> states that he found clusters containing as few as 

 G eggs and gives the number as ranging from 6 to 20. These hatch in about a 

 week, each larva emerging from the upper half of the egg and feeding takes 

 place in colonies on the upper layers of the leaf tissue, resulting in irregular, 

 unsighth', denuded areas. As the larvae become larger they separate and feed 

 independently on either side of a leaf. 



In the latitude of New Jersey, many become full-grown about the third 

 week of June, pupation taking place on the upper or under leaf surface. This 

 stage lasts about one week, the beetles appearing the last of June and first part 

 of July. There are at least two generations in New Jersey. During the middle 

 and last of June it is possible to find all stages of the insect except eggs. 



Chittenden;, records the adult. as attacking plants belonging to botanical 

 families not at all related to its normal food plants such as aquatic species of 

 Nymphaea, Sagittaria, Brasenia, Nuphar and mentions basket willow and beans. 

 He further states that it frequently has received mention under the name Gal- 

 eruca sag'Mariae Gyll, and is evidently of foreign origin, being found abundantly 

 in northern Europe, and Siberia. In this country it has been recorded from 

 Texas, California, Oregon, Indiana and occurs from the Hudson Bay region 

 southward to the District of Columbia and Mrginia. It is, therefore, a well 

 distributed species. Both .Schauppi and MacGillivray, have described the 

 early stages and the hitter's descriptions being the most detailed are given 

 below together with additional material in brackets which it was thought de- 

 sirable to add. 



Egg. — ^(Length 0.9 mm. Width 0.5 mm.) "Oblong or short cylindric with 

 smoothly, obtusely rounded ends; yellow, shining." (The surface is sculptured 

 with hexagonal markings having depressed centres.)  



Larva. (Length 7 to 8.5 mm. Width about 1.8 mm.). Head black; the 

 antennae mere tubercles, three jointed; the labrum three-sided, the distal and 

 lateral margins in the form of a continuous convex curve constituting one side, 

 the repiaining sides formed by the proximal end of the labrum with an angle 



1. The Coleoptera of Indiana, p. 1169. 



2. Bull. 68, N. Y. State Mus., 1903, pp. 325-326. 

 3.' Bui. 54, U. S. D. A. Bur. Ent., p. 58, 1905. 



4. Bui. Brook. Ent. Soc, Vol. VI, p. 54. 



5. Loc. cit. 

 October, 1920 



