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banida3. To tlio first-named family belong the notorious black fly 

 and buffalo gnat, — the latter recently the subjec tof elaborate study 

 by the United States Entomological Department. The larva of a 

 very similar species (perhaps the same as one or the other) is 

 very common in winter and early spring under rocks and wood in 

 spring-fed streams in Illinois, but the tiies are not known to dam- 

 age stock in this region (Central Illinois). The larvt^e of this fam- 

 ily are eaten by trout, and occur in the stomachs of other smaller 

 fishes. They were supposed at one time to entangle and destroy 

 young fishes in a fine silk web which they spin over surfaces upon 

 which they live. The pupje live in leathery cases attached to the 

 underside of stones and other objects in the water. The adult fly 

 emerges under water in the spring of the year. Cedar Creek is 

 exactly suited to these insects, and we should expect to find them 

 there at the proper season. 



The families Culicidse and Chironomidse contain the mosquitoes 

 and gnats. The larvjie are small, elongated, more or less cylindrical 

 worm- like creatures, with w^ell-developed head and often complicated 

 respiratory and tactile structures. The pupae of the Culicidse are 

 active, but take no food. The larvas occur in water at all times of 

 the year, so that in all probability a succession of broods are 

 reared each season. Some species, at least, are found in water when 

 cold weather comes in the fall and doubtless remain in the larval 

 condition till the next season. The eggs are placed in small masses 

 on the surface of the water, where they float till the larvae emerge. 

 The food is believed, commonly, to be decaying organic matter, so 

 that the larvae have been thought to offset in a measure, as fish- 

 food and as scavengers, the inflictions of the adults. They are 

 extremely common, and may be captured at night in surface-nets 

 literally by the pint. They swim by alternately flexing and ex- 

 tending the body, hence the name wrigglers. 



The family Tabanidae (the horse flies) contains a number of 

 species with aquatic larvae. The latter are large, with cylindrical 

 body tapering towards the extremities and consisting of twelve 

 segments. Color whitish, body-wall rather firm. Length as much 

 as 1.50 inch. The eggs, which are elongated, smooth and shining, 

 and of a dark color, are deposited in masses by the flies on rushes 

 and other aquatic plants in the latter part of summer. The larvae 

 live during the winter in the water, lurking about under submerged 

 wood or refuse. They are carnivorous, and with their strong 

 mouth parts can inflict a severe bite. From their strength and 

 activity they must destroy great numbers of the smaller aquatic 

 animals. One kept by the late B. D. Walsh, fed upon a number 

 of mollusks, pushing its way into the shells as far as it could, as 

 it devoured the owners. Notwithstanding their aggressive ways, 

 quantities of them are sometimes taken by the channel catfish 

 {IcfdliirKS punctcdus), and they are eaten, at least occasionally, by 

 bull pout. 



