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indurated that the worm is incapable of making the slightest motion ; 

 but on covering them with a wetted cloth, the surface again in a 

 short time becomes pliant and yielding ; and if pressed with a needle, 

 the animal writhes, and sometimes turns itself over to escape from 

 the annoyance. I doubt whether it ever moults, or casts off its skin, 

 between its egg and its pupa state ; but my observations have not 

 been sufficiently exact and prolonged to speak positively upon this 

 point. 



This is the form in which the insect passes the autumn and winter. 

 The accounts of writers disagree as to where the worm remains 

 during this period ; in fact few of them speak distinctly upon this 

 particular point. Mr. Kirby, however, describes the worm as still 

 continuing in the heads of the wheat ; but as a considerable portion 

 of them are missing, he thinks these have been destroyed by para- 

 sitic enemies. He says, " I have seen more than once, seven or 

 eight florets in an ear inhabited by the [active] larvae, and as many 

 as thirty in a single floret, seldom less than eight or nine, and yet I 

 have scarcely found more than one pupa [dormant larva] in an ear, 

 and had to examine several to meet with that." Mr. Gorrie, on the 

 other hand, asserts that the maggots quit the ears of the wheat by 

 the first of August, and enter into ihe ground, where they remain 

 through the winter. Mr. Shirreff", also, from finding the fly much 

 more abundant in fields where wheat had been grown the preceding 

 year than it was in other fields, entertains the same opinion. Now 

 the truth is, Mr. Kirby and Mr. Gorrie are both right. A portion of 

 the larvae leave the grain before it is harvested, and descend to the 

 ground, where I have found them, under mouldy fragments of straw 

 on the surface, or buried a half inch or less within the soil. I thus 

 found them, common in the field already spoken of as examined on 

 the 16th of June, a few days after the grain was harvested ; and 

 also early in March, in a field in which wheat was grown the pre- 

 ceding year, that had been somewhat injured by the fly. Another 

 portion of these larvae remain in the heads of the wheat, and are 

 carried into the barn, where they may readily be observed upon the 

 threshing-floor, and found in quantities among the screenings of the 

 fanning-mill, a considerable portion of which sometimes consists of 

 these worms. Thence our farmers kindly empty them out at the 

 door of the barn, where most of them doubtless find among the litter 



