552 



AN INTRODUCTION TO ENTOMOLOGY 



(Fig. 677). For further details regarding the venation of the wings 

 in this order, see "The "Wings of Insects" (Comstock '18 a). 



The metamorphosis is complete. The larvas are caterpillar-like, 

 with three pairs of thoracic legs and with or without abdominal pro- 

 legs. The pupae are exarate, that is, the wings and legs are free, as 

 in the Coleoptera and H^-menoptera. 



This order is represented in our fauna by six genera ; these can be 

 separated by the following table : 



A. With well-developed wings. 



B. Wings long and narrow; ocelli present. 



C. Tarsi with a single claw, and fitted for grasping Bittacus 



CC. Tarsi with two claws, and not fitted for grasping. 



D. Tarsal claws toothed Panorpa 



DD. Tarsal claws simple Pan6rpodes 



BB. Wings comparatively wide, with many cross-veins extending from the 



subcosta to the costa; ocelli wanting Merope 



AA. Wings wanting or imperfectly developed. 



B. Without ocelH; small insects, less than 6 mm., in length BoREUS 



BB, Ocelli present; body about 20 mm., in length Apterobittacus 



Panorpa or the scorpion-flies. — The most common members of 

 this order belong to the genus Panorpa, of which there are nearly 

 twenty described 

 North American 

 species. Figure 678 

 represents a female 

 of this genus. In 

 our more common 

 species the wings 

 are yellowish, spot- 

 ted with black. The 

 males of this genus 

 are remarkable for 

 the peculiar form of 

 the caudal part of 

 the abdomen (Fig. 

 679). This at first 



sight reminds one of „. ._ . . . „ 



the corresponding "^^^^Xl ' 



Fig. 678.— Pan- 

 orpa, female. 



Fig. 679. — Abdomen of 

 Panorpa rufescens. 



last two segments 

 of tarsus of Bittacus, ap- 

 posed; c, last three seg- 

 ments of tarsus of Bittacus. 



part of a scorpion, 

 and suggested the 

 common noxne scor- 

 pion-flies for these 

 insects. But in reality the two are very different ; the last segment 

 of the male Panorpa, instead of ending in a sting, like that of a scorpion, 

 is greatly enlarged and bears a pair of clasping organs. The tarsal 

 claws are toothed (Fig. 680, a). 



The adults are found resting on the surface of foliage of rank 

 herbage growing on the banks of shaded streams and in damp woods 

 where there is a luxuriant undergrowth of herbaceous plants. They 

 feed on dead or injured insects and upon fruits; it appears that they 

 rarely if ever capture living prey. 



