Agapetus pupae were found dioring each month except July. From a gross 

 analysis of the data, more specimens of Agapetus seem to be in the pupeJ. 

 stage during the winter months, and probably a greater proportion of these 

 animals emerge in early spring. 



Occasionally other Trichoptei^, including Psychomyia , Brachy - 

 centrus, Leptocerus , LeptoceHa , and Polycentropus were fo\ind. 



Plecoptera . The stoneflies are an ancient, primitive order 

 of insects which undergo incomplete metamorphosis. The succession is 

 egg to nyniph to adxilt. All of the nymphs of this order are aquatic, and 

 all but a few require running water for their development. The develop- 

 ment from egg through adult may take from one to three yeeurs. Most stone*- 

 fly numphs are phytophagus, or plant eaters, but members of the family 

 Perlodidae axe csLmivorous. This order of insects indicates cold, clean 

 water conditions. Stations at miles 256.3, 2i4-l, and 229.8 produced the 

 greatest nxambers of species and individusQ-s . 



The family Pteronarcidae is represented in California by two 

 species, Pteronarcys califomica and P. princeps . These are extremely 

 large-sized nyxnphs (up to two inches) , and their immatiire stages may take 

 two or three years for complete development. The species found during 

 the present survey was probably P. califomica . 



The two dominant members of the family Perlodidae fovind during 

 the survey were of the genus Isogenus . One of these, Isogenus ( isogenoides ) 

 has not previously been reported from California. 



Members of the family Nemouridae are phytophagous. The nymphs 

 of the several subfamilies are difficiilt to identify, especially the 

 Capniinae. They are primarily small, winter-emerging species. The taxo- 

 Domic problems are greatly increased when eidults as well sis imma ture s 



are not collected. 



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