86 
BULLETIN OF THE BUREAU OF FISHERIES. 
per cent were in the 20-25 m. stratum. A limited number of rotifers, consist ing of 
Anurxa aculeata and Notholca longispina, was found in the 20-30 m. stratum, and a 
small number in the 30-35 m. stratum. (See Table 12, p. 127, and figs. 11 and 12.) 
Ceratium was distributed throughout the lake, with three-quarters of it in the 
upper 10 m. 
Several strands of Melosira and Tabellaria were found in the 50-55 m. stratum. 
DIURNAL MOVEMENT OF PLANKTON CRUSTACEA. 
Night catches of net plankton were taken on August 26 and 27, 1911, for the 
purpose of ascertaining whether there was any marked diurnal movement of the 
plankton Crustacea. Table 12 (p. 127) shows that there was an appreciable upward 
movement of the Cladocera and of the Copepoda. 
