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INJURIOUS INSECTS ANJ3 FUNGI. 



[March 1895. 



grown in fields infested with wireworms, in order to starve 

 them out. Recent experiments, however, made in America at the 

 Cornell University Agricultural Experiment Station by Messrs. 

 Comstock and Slingerland, do not indicate that a crop of mustard 

 will render the soil so free from wireworms that the succeeding 

 crop will escape their ravages. Hop plants are frequently very 

 seriously injured by wireworms. When they have got into the 

 fibrous roots of these plants it is impossible to get at them, and 

 they bite off the shoots as fast as they make their appearance, 

 and eat the softer parts of the roots. In some old hop grounds 

 they have been most troublesome in this way. It was considered 

 that the backwardness of the bine, and the small " spindly " size 

 of the bine that came from the hills or plant centres, were due 

 to natural weakness or age, but examination showed that wire- 

 worms were the cause of the trouble. 



In newly planted hop grounds, wireworms are often most 

 destructive, eating off every shoot, checking growth, and some- 

 times killing the stock outright. 



Wireworms are more to be dreaded than most other insects, 

 because they feed upon stems and roots at all times and seasons 

 of the year, except during very hard frosts, when they go down 

 deep into the earth. As they live from three to five years in 

 the wireworm stage, their work of mischief is of long dura- 

 tion. Curtis says, on the authority of Bjerkander, that life in 

 the wireworm stage continues for five years ; but this of course 

 must depend greatly upon circumstances as to food supply and 

 other conditions. 



The wireworm is the larva of a beetle called " click " beetle, 

 because when held by one end it bends its body and produces a 

 clicking sound, and when placed on its back it jumps up and 

 makes a peculiar click. 



The most common species of the beetle, Agriotes lineatus 

 (Figs. 1 and la), is three-eighths of an inch long, and its 

 wing expanse is slightly over half an incli. Its thorax is 

 tawny ; the wing cases are brown, with lines of yellowish brown. 

 The antennae are reddish yellow, and the legs brown. 



Agriotes sputator (Figs. 2 and 2a) is not so large as 

 Agriotes lineatus. It varies in colour from brownish black to 

 chestnut, and has grey down upon it, with j^ellow antenoEe and 

 brownish yellow legs. 



Agriotes ohscurus (Figs. 3 and 3a) is rather larger than 

 Agriotes lineatus, tawny to brown in colour, with dark thorax 

 and reddish legs. 



These beetles are found under stones, at the roots of grasses, 

 upon grasses and various flowers and trees, in hedges and fields, 

 and upon reeds. They fly well, and lay eggs either on grasses, 

 corn plants, and weeds, or in the earth. Taschenberg says 

 that the beetles live all the winter in places of shelter and 

 concealment, and that pairing takes place in the first warm 

 days of spring. The larvse from the eggs live in the earth, near 

 the roots of plants on which they feed. 



