114 



Pamela S. Dolin and Donald C. Tarter 



A 



d 



40% -i 



30% 

 207,, 

 10% 

 0% 



50% -. 

 40% - 

 30% 

 20% H 

 10% 

 0% 



A 



Head Width (mm) 



Fig. 1. Head-width frequencies at monthly intervals of Chauliodes rastricornis 

 larvae from Greenbottom Swamp, Cabell County, West Virginia. Number in 

 parentheses after month is sample size. 



larvae to pupate in the drier environment before emerging as adults. 



Larval food habits. — The following taxa were found in the fore- 

 guts of Chauliodes larvae (Dolin 1980): ostracods, cladocerans, copep- 

 ods, amphipods, odonates, rotifers, dipterans, and the alga Tribonema. 

 Detritus and unidentifiable materials were also found. 



Based on a yearly mean, organic detritus ranked first (96%) in fre- 

 quency of occurrence in C. rastricornis, and ostracods (26%) were 

 second. Chironomids were found with a frequency of 16 percent. Based 

 on a yearly mean, organic detritus ranked first (82%) in frequency of 

 occurrence in C. pectinicornis, and ostracods (14.5%) and cladocerans 

 (14.5%) ranked second. 



Copepods were found only in winter in both fishflies. The unidenti- 



