AGRICULTURAL TEXT-BOOK. 70 



Germany into Long Island, R. I., by the Hessian troops, under Sir W. 

 Howe, in 1776. Thence it gradually spread over the Southern parts of 

 New York aud Connecticut, at the rate of fifteen or twenty miles ayear. 

 It was found west of the Alleghany Mountains, in 1797. In many 

 places, the culture of wheat was abandoned in consequence of its rav 

 ages. The body of the perfect insect measures about one-tenth of an 

 inch in length, and the wings expand a quarter of an inch or more. 

 Two broods are brought to maturity in the course of a year, and the 

 flies appeir in the spiing and fall In the latitude of New England, the 

 female begins to lay its eggs on the blade of the young wheat at the 

 end of September, or beginning of October. In four to fifteen days 

 the egg hatches ; the maggot, of a pale red color, crawls down the leaf, 

 and works its way between it and the main stalk, passing down till it 

 comes to a joint, just above which it remains, a little below the surface 

 of the ground, with the head towards the root of the plant. Here it 

 rests till its tiansformations are completed. It inether eats the stalk, 

 nor penetjates within ir, but lies lengthwise upon its surface, nourished 

 wholly by the sap. As it increases in size, it becomes imbedded in the 

 side of the stem, by pressure. If two or three are fixed in this manner 

 they frequently ctuse the plant to fall down and die. In five or six 

 weeks they grow to full size tbrue-twentieths of an inch in length. 

 About the first of December, they harden and change to a bright chest 

 nut color; in which Jorm they are commonly likened to a flix seed. 

 In this state, they gradually change to a fly, and appear again as such 

 at the end of April or beginning of May. Very soon after, they are 

 ready to lay their eggs on the leaves of the wheat sown in the previous 

 fall, or the same spring. In three weeks they entirely disappear from 

 the field. Undergoing the same changes, the maggets from these eggs 

 take the flax-seed form in June and July. In this state they are found 

 at the time of harvest, and when the grain ia gathered they remain in 

 the stubble in the fields. Some, however, are carried to the barn 

 The principal migrations of the flies t;ike place in the middle of Au 

 gust and September. 4. In 1843, Miss Morris discovered in Pennsyl 

 vania, another species of the Hessian Fly. (Cecidomyia culmlcola.) It 

 differs in its habits from the former, by depositing its eggs early in June 

 in ths grain. The egg remains unhatched till the gain is sown and 

 germinates, and the maggot soon eats its way into and burries itself in 

 the straw. Here it remains till it is ready to assume the flax-seed form, 

 and then, emerging, fixes itself to the outside of the stalk. It has since 

 disappeared from the locality, but may probably be met with else* 

 where, being mistaken for the first species. 



