0,1 the IVhcat-midge. 37 



Former observers have noticed the fact, that some of the larvse 

 (or maggots) quit the ears in which thej have been feeding in 

 order to bm'j in the ground^ where it is supposed they remain 

 until they change to flies ; whilst other larvae remain in the ears, 

 and prepare for themselves a little case or covering in which they 

 pass the winter. This case looks very much like an outer skin, 

 as though the larvae had contracted itself, and become detached 

 from its skin without shedding it ; and upon this case all the 

 markings of the body are impressed. The exact nature of this 

 case I must leave it to entomologists to decide; but of the fact 

 here alluded to I have had ample confirmation. 



In my report last year I offered a conjecture, that those larvae 

 which entered the ground had been '' ichneumonized," whilst 

 those which remained encased and in the ears would be found 

 uninjured, and would turn to flies in the spring. I have carefully 

 preserved specimens cf each kind : those which spontaneously 

 quitted the ears were allowed to bury themselves in sand ; and 

 those which remained in the ears were kept apart. I collected 

 some hundreds of the latter description from the barns in the 

 neighbourhood, in a manner I shall presently describe. Not one 

 of either batch have changed to flies, or even produced me any 

 specimens of the little ichneumon which plays so kind a part in 

 diminishing the numbers of the midge. Mr. Curtis, to whom I 

 forwarded specimens, has been equally unsuccessful with myself. 

 In a letter from him, dated the 30th of June, I find the following 

 remarks : — "■ I took infinite pains in nursing the different ears of 

 wheat in which the Cecidomyia larvae were, and at present they 

 have produced nothing. I have not been able to ascertain the 

 state of mine, but if yours be juicy, they will no doubt produce 

 either the midge or a parasite in due time. I think it very 

 possible that different things may have been confounded, for with 

 the greatest care I find myself often perplexed by the appearance 

 of some unexpected insect, where a totally different one was 

 expected. Your Cecidomyiae may be retarded by being unas- 

 sisted by heat or wet, as in nature; or they may be all females; 

 or another species ; but I do not despair of your breeding them." 

 This account will be sufficient to show practical men the great 

 difficulty which frequently attends the elucidation of some ques- 

 tions in natural history. 



I proceed now to detail the observations I have made on those 

 larvae which remained encased and in the ears ; and if it should 

 hereafter be ascertained that these do assume the fly state, I think 

 an easy method may be contrived for considerably diminishing 

 their numbers. 



I had selected ears of wheat from several fields in this parish 

 shortly before the harvest of last year. Upon picking them to 

 pieces about a month afterwards, I found that every field from 



