Contrihutious to Our Knowledge of the Freshwater Algae of Africa. 71 
regards the cell-contents, whilst the presence of discoid chloroplasts is 
undoubted, they were not nearly as numerous as shown by Lenimermann. 
Definite ring-shaped paraniy Ion- grains were also not recognised, but a large 
central nucleus was visible in several specimens, one of which is shown 
in Fig. 29, B. The shape exhibited by this individual was not uncommon, 
but the type represented in Fig. 29, G, which comes nearer to Lemmermann's 
figure and description, was also frequently seen. The delicate spiral striation 
of the periplast was very prominent. The dimensions were : long., 70-81 //. ; 
lat., 18-20 
4. ? Eugleyia terricola (Dang.), Lenimermann, loc. cit., p. 125, fig. 187. 
(Fig. 29, D.) 
Sample 161 (rather rare). 
Side by side with E. viridis and the form called E. proxima above there 
occurred another very slender species, the individuals of which were often 
roughly cylindrical, though sometimes of the form shown in Fig. 29, I). 
In a very few cases a small number of band- shaped chloroplasts were 
recognisable within the cell -contents and one of these specimens possessed 
a short flagellum (Fig. 29, D). These features and the presence of small 
rod-shaped paramylon-bodies are the grounds for referring these specimens 
to the above species, in the hope that a local observer may be able to 
verify the determination on living material. The spiral marking of the 
periplast was very faint and delicate. The dimensions were : long., 54-60 /x ; 
lat., 10-12 /X. 
(Note. — Indeterminable material of this genus was also present in 
samples 67, 99, 340, and 346.) 
Genus PHACUS Dujardin. 
1. Phacus ]}leuronectes (O. F. M.), Duj. ; Lemmermann, loc. cit., p. 138, 
fig. 236. 
Sample 338 (rare). 
Previously recorded from Cape Town (Fritsch). 
2. Phacus oscillans, Klebs ; Lemmermann, loc. cit., p. 141, fig. 225. 
(Fig. 29, E.) 
Sample 338 (rare). 
Long., 26 fji ; lat., 10 /x. 
Relatively few specimens of this form have been seen but they ail 
exhibited the above dimensions. They also agree with Klebs' form in shape, 
the possession of a single large paramylon-grain, and the spiral striation of 
the periplast. 
