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ticeable; others being present but not in large numbers. The Turnip Flea-beetle 

 (Phyllotreta vittata) was abundant in the rootfields and early in the season did 

 considerable damage to the yoimg urnipst. Another pest present during June and 

 July was the Wavy Flea-beetle (P. sinuata). This insect is interesting as it has 

 probably not befo're been reported as a pest in the province. It is an introduced 

 species wide-spread m Europe. In 1889, Horn described it as occurring in the 

 New England States south to Georgia and west to Missouri. Sanderson speaks 

 of it as feeding on the wild pepper grass (Lepidium virginicum) of the middle 

 and southern states. It entirely destroyed the cress and caused considerable loss 

 among the radishes in a small vegetable garden at the College. The adult insect 

 is hardly distinguishable from P. vittata. It is, however, larger than the latter, 

 and the inner margin of the basal portion of the yellow stripe is nearly parallel 

 to the suture, while in vittata it is incurved. In sinuata the fifth joint of the 

 antennae of the male is much larger than the corresponding joint in the Turnip 

 Flea-beetle. The larva is a small six-legged grub, greenish with numerous black 

 tubercles on the body segments, and with a black head and pronotum. It mines 

 into the leaves of the host plant, destroying the mesophyll tissue. When ready to 

 pupate it falls to the ground into which it burrows, builds a protective cell around 

 itself and changes into a small yellow pupa. 



The broods evidently overlap as both larvae and adults w-ere found feeding 

 on the leaves at the same time. A small hymenopterous parasite was reared from 

 the larvae of this insect. 



Potatoes suffered severely from two flea beetles. The Potato Flea-beetle 

 (Bpitrix cucumeris) was inost abundant, but there were also large numbers of 

 Systoia hudsonias feeding on the leaves. 



It was impossible to separate the amounts of injury caused by these two 

 insects. 



The Cabbage Butterfly {Pontia rapac) was extremely abundant on cabbage, 

 cauliflower and other cruciferous plants. 



Its parasites, however, were equally active. The ones which did most eft'ect- 

 ive work were the chalcid Pteromalns puparum and the Braconid Apantcles 

 glomeratiis. 



The Cabbage Root-maggot (Phorbia brassicae) caused considerable reduc- 

 tion in the yield of early cabbages. From the pupae of this insect I reared a 

 Cynipid parasite Tryhliographa anthomyiae. There were also present in the in- 

 fected soil large numbers of the predaceous staphylinid Aleochara nitida which 

 preys on the maggot. A species of Trombidium is known to feed on the eggs 

 of the cabbage root maggot; such a mite was found in abundance in the inefcted 

 fields, but it was not observed eating the eggs. As usual only the early cabbages 

 suffered. 



The turnips of the experimental plots were attacked last season by Phorbia 

 ftisciceps, an Anthomyian very much resembling the cabbage root-maggot. It is 

 almost impossible to distinguish the female of fusciccps from that of brassicae. 

 The only reliable differentiating character is to be found in a comparison of the 

 hind legs of the male. In P. Jusciceps there is a row of "short, rigid, bristly, 

 hairs of almost equal length on the inside of the tibia. In the case of the cabbage 

 maggot the male bears a characteristic tuft of long hairs at the base of the hind 

 femur. 



The Beet-leaf Miner (Pegomyia vicina) attacked the spinach in the spring 



