OF THE THIRD TANGANYIKA EXPEDITION. 185 
oribus, cum polis attenuatis et acutis ; cytoplasmate homogeneo et pallide 
cruginoso. 
Long. cell. 75-88 ш ; lat. cell. 1:8-2*5 д. 
Victoria Nyanza.—In plankton, near Bukoba (21 Apr. 1905 ; no. 252). 
D. africana is distinguished from all other species of the genus by its 
stellate colonies of elongated cells, which are suddenly bent round each other 
in the middle after the manner of some forms of Ankistrodesmus falcatus, 
(Corda) Ralfs. In the length of its cells this species agrees with D. acicu- 
laris, Lemm. (in Ber. Deutsch. Bot. Ges. xviii. (1900) p. 309), but differs in 
the bent cells, forming star-shaped colonies, and in the absence оЁ the bright 
refractive granules from the cytoplasm. 
Genus MERISMOPEDIA, Meyen. 
349. MERISMOPEDIA GLAUCA, ( Ehrenb.) Ndg. Gatt. einz, Alg. (1849) p. 55, 
t. 1 p. fig. 1. 
Nyasa.—On shores and among Utricularia, Domira Bay (19 June, 1904 ; 
nos. 17 and 579). 
Victoria Nyanza—Among Utricularia, near Entebbe (1 May, 1905: 
no. 620). 
Tanganyika.—In plankton, near Baraka (24 Feb. 1905; no. 240). 
350. MERISMOPEDIA PUNCTATA, Meyen, 1839 ; Rabenh. Fl. Europ. Alg. ii. 
(1865) p. 57. 
Nyasa.—In swamp, Karonga (2 July, 1904; no. 34). 
Victoria Nyanza.—Near Entebbe (1 May, 1905 ; no. 620). 
Tanganyika.—In plankton, near Chamkaluki (15 Nov. 1904 ; no. 160). 
351. MERISMOPEDIA .ERUGINEA, Breb. in Kütz. Spec. Alg. (1849) p. 472. 
Tanganyika.—In plankton, Lofu (6 Oct. 1904 ; no. 130), and near Sumbu 
(13 Oct. 1904 ; no. 138). 
352. MERISMOPEDIA ELEGANS, А. Br. т Kütz. l. ce; Rabenh. РІ. Europ. 
Alg. п. (1865) p. 57. 
Tanganyika.—In plankton, Vua Harbour (29 Oct. 1904 ; no. 150). 
Var. REMOTA, var. n. 
Var. cellulis ut in forma typica sed remotis, coloniis plus minusve sub- 
irregularibus. 
Diam. colon. (cell. 32-128) 52-146 ш; diam. cell. 7-9 p. 
Tanganyika.—In plankton, near Baraka (24 Feb. 1905 ; no. 240). 
The cells were similar in size and colour to those of М. elegans, but were 
more or less remote from each other in the enveloping jelly. The colonies 
were also more irregular than any I have previously observed of M. elegans. 
A few of the cells in each colony possessed a single dark granule, very 
probably of the nature of a gas-vacuole. 
