OF PHILADELPHIA. 



several very acute claws. Poisers, pale nearly as long as the 

 thorax, with a suboval capitulum. Breast sometimes fulvous. 

 Abdomen brownish. 



Female. — Antennae longer than the thorax, the joints some- 

 what oval, not separated by filaments. Abdomen elongate-oval, 

 above rectilinear, beneath somewhat ventricose, fulvous, with a 

 dorsal and ventral black vitta widely interrupted by the sutures. 

 Tail more or less acute in the dead specimen in proportion as the 

 oviduct is exserted. 



Length rather more than three-twentieths of an inch. 



Eggs elongated, linear, pale fulvous. 



Larva. — Body somewhat fusiform, whitish ; tail acute, rather 

 abruptly attenuated ; head incurved and attached by the mouth ; 

 above hyaline, exhibiting an internal, abbreviated, visceral, green 

 line ; beneath with opaque white clouds, which in the young ani- 

 mal are perfectly separate and about nine on each side, with an 

 intermediate series of smaller ones ; as the larva advances to its 

 full stature, these unite so as to exhibit the appearance of regular 

 transverse segments ; near the anterior extremity are the rudiments 

 effect resembling obsolete tubercules, or crenulse ; when taken from 

 the culm it is almost inert, exhibiting very little motion to the eye. 



Length three-twentieths of an inch, breadth one-twentieth. 



Pupa. — Resembles the mature larva, but is of a dark reddish- 

 brown color ; and appears perfectly inert. 



This well known destroyer of the wheat has received the name 

 of " Hessian Fly," in consequence of an erroneous supposition, 

 that it was imported in some straw with the Hessian troops dur- 

 ing the revolutionary war. But the truth is, it is absolutely un- 

 known in Europe, and is a species entirely new to the systems — 

 being now for the first time described. The insect described by 

 Mr. Kirby in the Trans. Lin. Soc. of Lond. vol. iv. p. 232, and 

 named by him Tipula Tritici, is without doubt of the same genius 

 with this, but specifically distinct. [47] 



The history of the changes of this insect, is probably briefly 

 this : — The eggs are deposited by the female in diiferent numbers 

 from one to eight, and perhaps more, upon a single plant of 

 wheat, and in so doing the parent exhibits another instance of 

 that provident care for the welfare of her offspring, which is so 

 strongly evinced by many of the insect race. The egg is not 

 placed at the axilla of either of the leaves indiflfereutly, but display- 

 1817.] 



