HYLESINUS TRIFOLII. CLOVER ROOT BORER. 377 



length. The pupa is 22 m m long and has two spinous projec- 

 tions on the top of the head, and two smaller anal projections. 

 The imago is black, with brown punctured elytra. It is 2 m m 

 (.08 of an inch) long. 



The beetle hibernates, usually as an imago, but also as a pupa 

 or larva. Mating occurs in early spring, when the female bores 

 into the crown of the plant and deposits five or six eggs. When 

 these hatch the larva feeds at first in the opening formed by the 

 imago for her eggs, but soon works downward forming tunnels 

 lengthwise of the main roots, which entirely destroys the plant. 



In September many pupae will be found in the upper part of 

 the galleries. 



Although as yet this beetle has not been found doing damages 

 in the United States outside a limited area in Hew York, it is 

 too much to hope that this will continue to be true. Surely 

 such enterprise as would carry the insect from Europe to America 

 can hardly be expected to permit it to remain stationary on this 

 continent. The fact that it has no parasites, as yet discovered, 

 to weaken its efforts or reduce its numbers, not only accounts 

 for its exceeding numbers in this country as compared with Eu- 

 rope, but also gives prophecy of wide extension and serious rav- 

 ages in the future. 



It is difficult to suggest satisfactory remedies for insects which 

 are so numerous and scattered as are these beetles. It is prob- 

 able, in fact the experience in New York already confirms the 

 suggestion, that they will not be equally destructive every year ; 

 that while they may ruin whole fields one season the very next 

 year they may be quite rare and far less injurious. The only 

 remedy thus far suggested is to plow the clover under when the 

 insects are discovered to be at work, and not grow clover for a 

 time. This green manuring would certainly be very excellent 

 for the land. Yet it is to be feared that the insects would take 

 to other herbage, possibly other leguminous plants, rather than 

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