Lake Maxinkuckee, Physical and Biological Survey 303 



These Ciilicid?e also furnish food for the dragon-flies and damsel- 

 flies ; the adult dragon-fly eats the adult mosquito, gnat, midge, etc., 

 while the dragon-fly nymph feeds just as voraciously on their wrig- 

 gler larvse. The larger fish feed upon the dragon-flies, both adults 

 and nymphs, and thus indirectly upon these Diptera. 



II. The Ephemerida. May-flies. 



These may-flies or shad-flies are all aquatic, and their nymphs 

 can be found everywhere in countless numbers amid the algae and 

 near the surface of the water. Several times during the early 

 summer the tow consisted almost entirely of these nymphs and 

 their cast skins from which the sub-imagos had emerged. 



These were the larger species having a limited period of emer- 

 gence, the adults of which suddenly appear in countless numbers 

 along the lake shore and as suddenly disappear. 



At such times the sub-imagos and imagos fairly covered the 

 screens at the doors and windows after nightfall, and there was 

 no difficulty in collecting a sixteen-ounce bottle full every evening 

 around the lantern on the wharf. In the morning the entire top 

 of the wharf would be found covered with the sub-imago skins 

 fastened as closely together as they could stand. 



But most of the species are not thus limited, and only a few 

 adults emerge at a time, the nymphs being taken commonly in the 

 tow during the entire summer up to the first of August. The lar- 

 vae are very active and swim about among the water plants, feed- 

 ing for the most part upon algse, including beside the plankton 

 scums, diatoms and coniervae. The larva lives from one to three 

 years, thus compensating in a measure for the short life of the 

 adult. 



Both larvse and adults are eaten by nearly every fish in the 

 lake, and thus constitute an important item in their food. 



In particular they are a favorite food with the crappie, the 

 redeye, the perch, the darters, the catfish, the suckers, and the 

 minnows. The fact to which Howard calls attention in his Insect 

 Book is worthy of repetition here in emphasizing the value of 

 these insects for fish food. Imitation shad-flies furnish one of the 

 best possible baits in regions where the real insects abound. The 

 flies known as duns, drakes, and spinners, which are used by Eng- 

 lish anglers, are imitations of Ephemerids. One of the best arti- 

 ficial baits at Lake Maxinkuckee is known as the Hildebrandt spin- 

 ner, in which the hook is covered with a tuft of feathers to simu- 

 late an Ephemerid. 



20—17618 



