stones across the xmderside which leaves an oi)ening at each end. Agapetus 

 extends head and legs out one end emd posterior prolegs or anal claws out 

 the other and crawls along the surface of larger stones feeding on the 

 algae and mosses growing there. VHaen ready to pupate, Agapetxis cuts away 

 the bridge at the bottom of its case and carefully seals the case to a 

 large stone. Inside, a reddish brown, bean-shaped chitenized covering 

 encloses the larva. How this develops is unknown, but presxomably the larva 

 secretes this material. One quick method of determining which pupal case 

 contains either Hydropsyche or Agapetus, since their cases are very simi- 

 lar in appearance, is this chitenized covering. Hydropsyche , as previously 

 stated, spins a cocoon of silken fibers, and the difference between the 

 two cases is at once apparent from the underside. 



Lepidostoma belongs to the fsunlly Lepidostomatidae . This animal 

 constructs a case that is a circular tapered tube of sand grains when 

 quite small. As the animal grows, however, flat peurticles of plant material 

 are substituted for sand, and the case becomes square in cross-section. 

 Contrasted with Agagetus, Lepidostoma has only the head and legs free, 

 while the anal claws secure the animal to its case. At pupation, each 

 end of the case is sealed with plant and stone material bound together 

 with silk. 



Ochrotrichia and Lepidostoma are fovind in greatest nxmbers in 

 the upper area of the upper reach (above mile 279.2), but also occur at 

 all the riffle stations. Agapetus apparently does best in the central 

 area of the upper reach (mile 279.2 to 253.4), and Hydropsyche occurs 

 more frequently in centreO. to lower portions of the upper reach (mile 

 279.2 to 229.8) . Hydropsyche pupeie were found during each month of the 

 survey, eO-though they were most prevalent between May and September. 



