38 



THE CLOVER SEED MIDGE— Cecidomyia leguminicola, Lint. 



Tlie firfet mention we have of this serious pest is in an article published in the organ . 

 of our Entomological Society of Ontario, the Canadian Entomologist^ in March, 1879, 

 contributed by Professor Lintner. Under the heading of " A New Insect Pest," he 

 says : " In the summer of 1877 my attention was called to some * worms' which had been 

 discovered in the heads of red clover {Trifolium iwatense), and were said to be preying 

 upon the seeds. They were found to be minute maggot-like creatures hidden within the 

 seed-pods, and entirely destroying the seeds which they attacked. Numbers of them were 

 subsequently detected in the examination of heads of clover taken from several localities 

 in the vicinity of Albany and in Warren County, N. Y. I was unable at the time to 

 refer the insect to any described species, or to find any record of a similar depredation on 

 clover seeds in this country or in Europe. 



"The following season (1878), additional examples of infested clover heads were 

 submitted to me which had been sent from Mr. George ^Y. Hoffman, President of the 

 New York State Agricultural Society, from Elmira, N.Y. A number of the larvae were 

 obtained from these heads, and their careful examination enabled me to refer them to the 

 Gecidomyidxx — of a species probably closely related to the well-known Wheat Midge 

 (Gecidoiiiyia destructor). Several of the larvje were preserved in alcohol, and the larger 

 number placed in a pot of damp sand, in which they speedily buried themselves for their 

 transformation." These larvae were of a pinkish colour, approaching orange, and about 

 one-twelfth of an inch long. In January of the same year. Prof. Lintner had announced 

 the appearance of this new destructive insect at the Annual Meeting of the New York 

 State Agricultural Society, and the discussion which followed brought out the information 

 that this insect had committed serious depredations on clover seed in several counties in 

 western New York during the previous summer, so that fields in some sections which had - 

 been kept for seed proved to be scarcely worth cutting. In July of the same year, Mr. 

 Lintner, in another communication to the Canadian Entomologist, announced the dis- 

 covery of the perfect insect which he had reared, and it proved to be — as he supposed it 

 would — a small fly, a species of Cecidomyia, to which he subsequently gave the name of 

 hguminicolu. Observations since made enable us to complete its history. 



How IT Spends the Winter. 



The insect passes the winter in the pupa or chrysalis state either on or under the 

 surface of the ground, and early in spring the fly escapes, when the sexes pair and the 

 female soon becomes ready to deposit her eggs. 



The Egg. 



The female, by means of a long ovipositor (see fig. 13, c), pushes the eggs down the 

 hairy tubes of the undeveloped flowers in the young clover heads almost as soon as the 

 flowers begin to form, which in Ontario would be during the early part of May. The 

 eggs are so small that it is almost impossible to discover them with the naked eye, their 

 length not exceeding the hundredth part of an inch. They are of a long, oval form, three 

 times as long as broad, with one end slightly larger than the other. They are of a pale 

 yellow colour when first laid, but become tinted with orange as the larva within matures ; 

 they are usually deposited singly, but sometimes in clusters of from two to five — as many 

 as fifty eggs have been counted in a single flower head. No estimate has yet been made, 

 to my knowledge, of the number of eggs which a single individual is capable of producing, 

 but doubtless this insect is very prolific. In about ten days the eggs hatch, when the 

 young larva works its way down the tube of the flower to the seed, upon which it feeds. 



The Larva, or Grub. 



The larvae when full grown are about one-twelfth of an inch Jong, usually of a bright 

 orange-red colour, occasionally paler and sometimes almost white. They are footless, and 

 have a wriggling, worm-like motion ; they affect the clover heads in the same manner that 



