132 МВ. С. 8, WEST ON THE FRESHWATER АТСА 
Family HYDRODICTY ACEJE. 
Subfam. PEDIASTRE.. 
Genus PEDIASTRUM, Meyen. 
144. PEDIASTRUM Terras, (hrenb.) Ralfs, in Ann. Nat. Hist. xiv. (1844) 
p. 469, t. 12. fig. 4.—Micrasterias Tetras, Ehrenb. 
Dispositio cellularum 4, 1+7, et 5+ 11. 
Nyasa.—On shore, Domira Вау (19 June, 1904 ; no. 17). In swamp, 
Kota Kota (20 June, 1904; no. 18). Swampy lake margin, Domira Bay 
(no. 579). 
Victoria Nyanza.—Among Utricularia, near Entebbe (1 May, 1905; 
no. 620). 
Tanganyika.—In swamp, Kituta (23 and 26 Aug. 1904 ; nos. 72 and 80). 
Floating on surface, Kituta Bay (26 Aug. 1904; no. 79). In swamp, Mbete 
(29 Sept. 1904; по. 108). Plankton, Lofu River (5 Oct. 1904 ; no. 123). 
Plankton, Baraka (24 Feb. 1905 ; no. 240). 
From Nyasa (по. 17) а coenobium was observed consisting of only three 
cells (Pl. 5. fig. 6). This is a very interesting condition directly intermediate 
in character between the two-celled ccenobia of Euastropsis and the simple 
four-celled ccnobia of Pediastrum. 
Var. LONGICORNE, Racib. 
Diam. coenob. 4 cell. (cum cornibus) 18-20 ш. (PI. 5. fig. 5.) 
Nyasa.— Plankton, Anchorage Bay (13 June, 1904; no. 9). 
145. PEDIASTRUM Boryanum, (Turp.) Menegh. Synops. Desm. in Linnea, 
xiv. (1840) p. 210; Ralfs, Brit. Desm. (1848) p. 187, t. 31. fig. 9 a. 
Nyasa.—Plankton, Deep Bay (24 June, 1904 ; по. 25). In swamp, Kota 
Kota (20 June, 1894 ; no. 18). 
Victoria Nyanza.—Among Utricularia, near Entebbe (1 May, 1905; 
no. 620). 
Tanganyika.—In swamp, Mbete (28 Sept. 1904; по. 108). Plankton, 
near Sumbu (13 Oct. 1904; no. 138). Plankton, near Kala (19 Nov. 
1904 ; no. 170). 
Var. RUGULOSUM, var. п. (Pl. 5. fig. 22.) 
Var. cellulis irregulariter cristatis, cristis valde irregularibus sinuatis et 
anastomosis. 
Diam. coenob. 150-192 р; diam. cell. 22-29 y. 
Victoria Nyanza.—Plankton, near Bukoba (21 Apr. 1905 ; no. 252). 
146. PEDIASTRUM INTEGRUM, Ndg. Gatt. einz. Alg. (1849) p. 96, t. 5 в. fig. 4. 
Diam. coenob. 28-67 p. 
Tanganyika.—Plankton, near Mbete (28 Sept. 1904 ; по. 109). Plankton, 
near Kala (19 Nov. 1904 ; no. 170). 
