45 



hairs. It has an interrupted dorsal stripe on the abdomen. The wings are 

 clear. It measures half an inch in expanse of wings, and a quarter of an 



inch in length of body. The mother tiy 

 lays her white oval eggs on the edge of 

 the sheath of the onion, near the ground, 

 seldom depositing more than six on one 

 plant. The eggs hatch in a few days, and 

 the maggots, which in general appearance 

 resemble those of the radish fly, work their 

 way downward, inside the sheath, to the 

 bulb. Having devoured one bulb they will 

 pass on to another. They may often be 

 found clustered on the outside of the bulb. 

 It takes them a fortnight to attain their 

 growth, and in another fortnight the perfect 

 flies appear. While the onions are yet very 

 3'oung soot and wood-ashes should be scat- 

 tered over the bed as a preventive, and 

 where the maggots are really working hot water should be applied to the bulbs 

 with a watering can. This will destroy the maggots without injuring the plants. 



For a more full account of this pest see Dr. Bethune's excellent article on 

 Remedies for Noxious Insects^' in the Society's 19th annual report. 



The Cabbage Fly {Anthomyia drassicce, Bouche). — The cabbage fly is ash- 

 grey. The male has three black longitudinal lines on the thorax, a black dorsal 

 line on the abdomen, and black bands at the edges of the segments. In the female 

 the lines on the thorax and the bands on the abdomen are wanting. 



The female fly lays her eggs at the junction of the lowest leaves with the 

 stem. The larvse eat the rootlets and penetrate the main root and the stock. 

 The plant speedily withers away. In wet seasons especially the insects are often 

 very destructive. 



It has been recommended as a preventive that, at the time of planting, the 

 roots and stems of the cabbage plants should be dipped in weak lye of ashes. As 

 a remedy Dr. Lintner tells us (1st Annual Report of Injurious and other Insects 

 of the State of New York. p. 190), " Watering the plants with lime-water has 

 been found to be of service in killing the larvae." 



The Root Fly (Anthomyia radicum, Linn). — The male of the root fly has 

 the thorax on the upper side, marked with three black longitudinal stripes and 

 three grey ones. The abdomen has a black dorsal line and is crossed with black 

 lines at the sutures. The female is lighter in colour and much resembles A. 

 hrassicce, but it has three fuscous longitudinal lines on the thorax. She lays her 

 eggs in the crown of the turnip or other root. These hatching, the ochre-coloured 

 maggots work down into the bulb. When full grown they leave the bulb and 

 pupate in the earth. The flies appear in the spring. 



The use of superphosphate as a manure will preserve the turnips from the 

 attacks of the fly. 



The Beet-Leaf Miner {Ghortophila hetarum, Lintner). — This is a small 

 fly, expanding four-tenths of an inch only. The body colour is grey. The thorax 

 has three dusky stripes. The wings have a brownish tinge ; and the legs are 

 black. It appears in June, and lays its beautifully reticulated eggs on the under 



Fig. 11. 



