1985] 
Pet try & Tarter — Baetisca Carolina 
367 
from October 1981 to September 1982. Nymphs were primarily col- 
lected from a sand and small stone substrate. Length-frequency 
distributions indicate a one year (univoltine) life cycle. Male and 
female nymphs exhibited the greatest growth in April and July. 
Females exhibit a definite size superiority. Monthly foregut analysis 
indicates that nymphs are primarily detritivouous, with other com- 
ponents of the diet including diatoms and filamentous algae. Two 
colormorphs, light and dark, are present in the population. As 
nymphal size increases, a greater percentage of the population 
exhibits light body coloration. Multivariate discriminant analysis 
was used to separate B. Carolina from the closely related B. berneri. 
Subimagos emerge in the field from mid-May through the end of 
August. A bimodal pattern of emergence was observed. Imagos 
emerged approximately 24 hours later. Direct egg counts ranged 
from 3271 to 5274 per female; the average was 4280. The correlation 
coefficient between fecundity and body size was 0.83. 
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