20 
Transactions of the Uoyal Society of South Africa. 
In view of the scanty nature of the material and of the absence of ripe 
oospores, the reference of this form to 0. imsillum is somewhat doubtful. 
Except for the larger dimensions, however, all the characters agreed with the 
diagnosis in Hirn. The oogonia were biconical-ellipsoid, with a wide median 
operculum, and the basal cell was hemispherical. Neither antheridia nor 
dwarf males were encountered, so that the present observations support the 
view that this species is dioecious and macrandrous, 0. pusillum has been 
recorded from Abyssinia by Lagerheim. 
2. Oedogonium pringshei^nii, CrsLmer ; Hirn, op. cif., p. 170, Tab. XXYII,. 
fig. 155. 
Sample 159. 
Diam. cell, veg., 15 /x, altit. usque 4-5-plo major ; diam. oogon., 39//,. 
Previously recorded from Little Namaqualand (G. S. West). 
3. Oedogonium sp. (0. varians, Wittr. et Lund.; Hirn, o]?. cit., p. 89,- 
forma ?). 
Samples 311, 812. 
Only sterile fi.laments and such as bore oogonia were observed. The 
form thus appears to be dioecious — a condition which is not unknown in 
0. varians (cf Hirn, p. 90). The oogonia were often pyriform, but in a few 
cases the shape was more elliptical ; there was an almost superior pore which 
was generally difficult to recognise. The basal cell was hemispherical which 
is not the type hitherto recorded for 0. varians. The dimensions were : Lat. 
cell, veg., 7-9 /x, long., 27-50 /x ; lat. oogon., 22-27 /x, long., 24-30 )u. 
(Note. — Sterile species of Oedogonium were also observed in samples 
17, 19, 20, 21, 29, 86, 327, 329, 330, 331, 334, 340, 341, and 342.) 
Genus BULBOCHAETE Agardh. 
(Note, — Only sterile material of this genus was present, viz. in samples^ 
86, 159, 311, 339, and 340.) 
{h) SIPHONALES. 
(2) YAUCHERIACEAE. 
Genus VArCHEEIA De Candolle. 
1. Vaucheria sessilis (Yauch.), De Candolle ; Heering, Suesswasseralg. 
Schleswig-Holsteins, etc., ii, Jahrb. d. Hamburg. Wiss. Anst., xxiv, 1906, 
p. 143. 
Sample 344 (f. reopens, Eabenh.). 
(Note.— Sterile material of this genus was encountered in samples 24, 66, 
and 334.) 
