INJURIOUS CADDICE FLY. I23 



'Culture, Washington, D. C, who informed us that the injury was 

 also new to him. As caddice flies cannot be classified beyond 

 the genus by the cases and larvae, we wrote to Mr. Miller to catch 

 some of the flies for us. Such thorough hand picking had been 

 done that probably no larvae were left to emerge, and though the 

 pond was watched during the season, no flies were taken. The 

 larvae sent us by Mr. Miller were dead when received so we were 

 not able to rear the flies. 



During August we were in Bar Harbor and visited the Mt. 

 Desert Nurseries and examined the pond. No caddice flies were 

 then on the wing. We arranged with Mr. Miller to transfer 

 -some of the case-worms to a tub in the house and try to rear the 

 ^ies. Later he informed us that no live case-worms could be 

 found. Should they give trouble again, we will investigate 

 farther. 



We sent some of the cases to Mr. Nathan Banks who thinks 

 they belong as placed below. To Mr. Miller, we made the fol- 

 lowing reply : 



"The case-worms you sent belong to the Order Trichoptera 

 (Caddice Flies), Family LimnephilidcB, Genus Limnephilus. It 

 will be necessary to have the flies to decide the species. I send 

 you a drawing of a species of caddice fly and wish you would 

 send me any related insects you find about the pond. 



"Caddice flies lay their eggs upon the surface of water plants. 

 The young make cases in which they live, or some species appro- 

 priate the hollow stems of water plants. Some of them are car- 

 nivorous and feed upon other insects, but most of them are veg- 

 etable feeders. But little is known about their food habits 

 excepting that many feed on water plants. The injury was 

 entirely new to me. There is no record of caddice flies having 

 been injurious to water lilies. They might commonly feed upon 

 our wild species and the habit be overlooked as the plants are not 

 of economic importance. They might have been in your arti- 

 ficial pond in some number and have been overlooked. It was 

 the unusual number that attracted attention. As you have con- 

 trol of the water level in the pond, there is no better remedy 

 than hand picking, or cleaning the pond in the winter. As you 

 have done a thorough job of hand picking, probably you will 



