Here the initial rearing densitiesvaried from 25.5 to 30.6 g L in experiment 2/93 (part II), and from 12.6 to 14.1 g L in experiment 3/94 (part II); the final rearing densities varied from 38.0 to 45.7 g L in expt 2/93 (part II), and from 30.7 to 45.4 g L in trial 3/94 (part II).