102 



but is not otherwise very different from (1). The posterior legs 

 are not so long and slender relatively and the fringe is less per- 

 fect. This form was taken from the bottom in Willow Slough. 



Trichoptera, pupa. 



A pupa of some species of this group was taken in "Willow 

 Slough sealed up in its cylindrical case of dead vegetable materi- 

 als. At the end towards which the head laid, a narrow slit had 

 been left for the passage of water for respiration. Judging by 

 the cast larval skin with this pupa, it cannot belong to either of 

 the two larvse described. 



ORDER NEUROPTERA. (Hellgrammites and Lace-wixg 



Flies. ) 



With four ample membranous wings with numerous longitudinal 

 and cross veins. Mouth with strong biting mandibles. Labial 

 palpi 3-jointed. Autennse filiform. Prothorax large and square. 

 Larvae with jointed legs, and a large head bearing free mouth 

 parts. Pupa inactive, with mandibles. 



The order contains two families, the larvae of which are very 

 different in habit. The lace-wing flies are throughout life terres- 

 trial, and are well known to gardeners and fruit-growers for the 

 good they do by devouring plant-lice. The hellgrammites or 

 crawlers are aquatic during the larva stage and feed upon other 

 water insects, such as case-fly and May-fly larv?e. They are them- 

 selves to some extent used by sportsmen as bait in catching fishes, 

 their tough skin rendering them easily disposed and retained on 

 the hook. They are furnished with seven or eight pairs of re- 

 spiratory filaments along the sides of the body for use in the 

 water, and have, besides, breathing pores (spiracles) which they 

 use when they leave the water to pupate in the earth. The tarsi 

 have two claws. The eggs are deposited in large, whitish discoidal 

 masses on the leaves of trees and on the sides of boats and barges. 



Oorydalis cormdus, Linn. (Hellgrammite.) 



< Walsh and Riley, Am. Ent., i, 61, 1868.) 



The larvfie and adult of this large insect often attract the atten- 

 tion of those who live on our rivers. The species is not often seen 

 in the interior of the State. Along the Mississippi River it 

 is very common, though its abundance is not commonly ap- 

 parent excepting during the egg-laying season. In August the 

 wood barges and boats in the bay were resorted to by the females, 

 and the masses of eggs were left in numbers upon the timbers. 



ORDER HEMIPTERA. (True Bugs.) 



Wings four, the front ones often thickened at the base Mouth 

 parts suited to taking liquid food, long, slender, and commonly 

 enclosed by a jointed beak formed of the modified labial palpi. 

 Prothorax free. Larva^ and pup.ie active, differing from adults only 

 in size and in the absence of wings. 



