170 ^H,E CANADIAN ENTOMOLOGIST 



fragile. Observations made on material collected showed the eggs hatched in 

 about four days. According to this observation the egg laying period doubtless 

 began at least by May 16th. 



The larvae enter the mid-rib through the puncture. They burrow in the 

 mid-ribs and extend their work down to the pith of the branches and main 

 stalk. Instances were observed where more than thirty larvae were found in a 

 leaf mid-rib two and one-half inches in length and one hundred and fifty in a 

 single plant. The larval period occupied about ten days- after which they 

 emerge from the stalk by boring small holes in the side of the stalk or branch; 

 Doubtleos each hole serves as a means of escape for several larvae as there 

 are apparently more larvae in a stalk than holes. The larvae drop to the 

 ground and pupate. 



The mature larva measures 4-5 mm., legless, white. Head lemon yellow 

 with dark brown tipped mandibles. The body is composed of 12 easily recognized 

 segments, each segment, especially those of the abdomen, is marked with 

 distinct ridges. 



Pupation occurs near the surface of the soil in brown, fragile pupal cells 

 made of earthen material. Each cell measures 5mm. in length. The pupal 

 period occupies about ten days. The pupa measures 3mm; white; scattered over 

 the thorax, head, beak and tip of femora are prominent brown spines. These 

 spines serve to keep the delicate pupa from touching the roughened surface of 

 the pupal cell. Shortly after pupation the eyes become jet black. As the pupa 

 grows older it gradually becomes darker. 



The adults of the seed stalk weevil were found in the field from June 16 to 

 July 10th. They are rather difficult to observe, due to the minuteness, color 

 and habit of "playing possum" upon the least disturbance. They can be readily 

 observed during the fore part of a still, warm day on the upper branches and in 

 the axils of the leaves of the seed stalks. 



Blatchley and Leng give a good description of the cabbage seed stalk weevil 

 in ''Rhyncophora of North America" p. 443. 



The insect undoubtedly hibernates as an adult although no trace of it could 

 be found after it had disappeared from the fields in July. 



In general the cabbage seed growers on Long Island either failed to recog- 

 nize this insect or confused it with the larval stage of the common cabbage mag- 

 got (Plwrbia brassicae Bouche). It is due to this confusion that Httle informa- 

 tion has been secured concerning its distribution and destructiveness in the 

 past. 



The distribution of this weevil in the cabbage seed field in the vicinity of 

 Mattituck seemed quite general during the past season. The information collected 

 was taken from a comparatively few fields although characteristic signs of the 

 presence of the insect were seen in nearly every field in that vicinity. 



The losses to the cabbage seed grower are due to the larvae burrowing in the 

 pith of the main stalks and branches thus weakening the plant and causing it to 

 break over or die prematurely. In either case the quantity and quality of seed 

 produced by an infested plant is inferior to that of a plant not infested. 



In order to learn to what extent the weevil occurs and to determine the losses 

 caused by it, counts were made in five fields. It was found that forty-seven 



