4S4 -MR. F. BALFOUR BROWNE ON THE EARLY STAGES IN THE 
the posterior end of the notochord was just turning upwards, 
the thickening below being visible. I never succeeded in 
keeping the larvag alive in the aquaria beyond this stage, 
conditions which were quite suitable for the larval Pike, 
Roach, and Stickleback being unsuited to the larval Perch. 
At this stage the fish was very long and thin, and the 
pectorals very large, and I should imagine that this species, 
unlike the Pike, Roach and Stickleback which skulk amongst 
the water weeds, swims in the open channels, its remarkable 
transparency supporting this idea. 
The other fresh-water species of the Perch family, the 
Ruffe or Pope ( Acerina cernua), I was unable to rear as I never 
succeeded in finding the eggs in nature, and I did not manage 
to obtain a ripe male at the time I had a ripe female. I only 
