Uy 
the two groups are not so disproportionate as the figures might 
seem to indicate. For each one of the Cladocera there are 95 roti- 
fers and almost 18,000 Protozoa. The latter are distributed as fol- 
lows: There are 9 rhizopods, almost 2,400 ciliates, and over 
15,000 flagellates for each one of the Cladocera. There are also 
about 86,000 plants for each of these Cladocera. Of these plants, 
64,000 are diatoms, 14,000 are Schizophycee, 9,000 Chlorophycee, 
while but 8 are desmids. The great abundance of diatoms, of 
green and blue-green algz, and of chloryphyll-bearing flagellates 
affords, it would seem, an abundant food supply for the zodplankton. 
If of the Mastigophora the colorless flagellates only be retained in 
the zodplankton, and the remainder—which are predominantly 
synthetic forms—be included with the phytoplankton, we find the 
latter outnumbering the analytic organisms (zodplankton) 18 to 1. 
Quantitative values in: the matter of food relationships are not 
readily determined except by a combination of the chemical and 
experimental method. These results: by the statistical method 
express, with more or less error, the equilibrium of the biological 
components in terms of the individual organisms. 
