160 МВ. С. S. WEST ON THE FRESHWATER ALG 
249, CoccoNEMA VENTRICOSUM, (Kütz.) nob.—F'rustulia ventricosa, Kütz. 
(1834). Encyonema ventricosum, Van Heurck. Е. cæspitosum, Kütz. (1849). 
Tanganyika.—On the shore, near Niamkolo (1 Aug. 1904 ; no. 44) and in 
Niamkolo Harbour (7 Sept. 1904 ; no. 87). 
250. CoccoNEMA GRACILE, (Rabenh.) G. S. West. Treat. Brit. Freshw. Alg. 
(1904) p. 299.—Encyonema gracile, Кафенй. 
Nyasa.—In swamp, Kota Kota (20 June, 1904 ; no. 18). 
Victoria Nyanza.—In swampy pool, near Bukoba (20 Apr. 1904 : no. 618). 
Tanganyika.—In plankton, Lofu River (5 Oct. 1904 : no. 123). 
251. CoccoNEMA CYMBIFORME, /Zhrenb. Infus. p. 225 (1888); W. Sm. 
Brit. Diat. i. р. 16, t. 23. fig. 220. 
Nyasa.—In plankton, Deep Вау (24 June, 1904; по, 25). Among Alg:e 
on rocks, Deep Bay (25 June, 1904: no. 26). Swampy lake margin, 
Domira Вау (19 June, 1904 ; no. 579). 
Victoria Nyanza.—Swampy pool, near Bukoba (20 Apr. 1905 : no. 618). 
In sheltered bay, near Entebbe (1 May, 1905 ; no. 620) : very numerous and 
with sporangial valves. 
Tanganyika.—In plankton, near Mbete (21 Sept. 1904 ; no. 105) and in 
Vua Harbour (29 Oct. 1904 ; no. 150). In swampy pond, Mrumbi (27 Dec. 
1905 ; по. 195). Among Utricularia, mouth of Malagarasi River (16 Jan. 
1905 ; no. 611). 
352. CoccoNEMA CistuLa, (Ehrenb.) W. Sm. Brit. Prat. i. p. 16, t. 23. 
fig. 221. 
Tanganyika.--Komba Bay (10 Oct. 1904 ; no. 134). Among Algæ scraped 
from bottom of Dr. Cunnington's dau (24 Jan. 1905 : no. 217). 
Var. MACULATUM, (Aütz.) Cleve, Synops. Navic. Dat. 1. (1894) p. 173.— 
Cymbella maculata, A. Schm. Atlas, t. 71. fig. 21. 
Victoria Nyanza.—In plankton, near Bukoba (21 Apr. 1905 : no. 252). 
Genus AMPHORA, Ehrenb. 
253. AMPHORA OVALIS, Kätz. Synops, Viat. (1833) ; Bacill. (1844) p. 107, 
‚5. figs. 35, 39 ; Rabenh. Fl. Europ. Alg. i. (1864) p. 91. 
Nyasa.—On shore, Domira Bay (19 June, 1904; no. 17). In swamp, 
Karonga (July, 1904 ; nos. 33 and 34). 
Tanganyika.—ln plankton, Mbete (28 Sept. 1904 ; no. 105), Komba Bay 
(11 Oct. 1904 ; по. 135), near Kala (19 Nov. 1904 ; no. 170), off. Kirando 
(1 Dec. 1904 ; no. 175), and near Baraka (24 Feb. 1905 ; no. 240). 
t 
254. AMPHORA COFEJEIFORMIS, (Ag.) Aditz. БасИ!. (1844) p. 108 ; Cleve, 
Synops. Navic. Nat. п. (1895) p. 120. 
Tanganyika.—In plankton, Komba Bay (11 Oct. 1904 ; no. 135). 
