OF THE THIRD TANGANYIKA EXPEDITION. 163 
265. NITZSCHIA AMPHIBIA, Grun. in Wien. Verhandl. (1882) р. 574 ; Van 
Heurck, Synops. Diat. Belg. (1885) p. 184, t. 68. figs. 15-17. ` 
Cellulze lanceolate cum punct. carin. 7 in 10 р: long. 35 ш ; lat. 10 д. 
Nyasa.— Abundant in scrapings off bottom of s.s. * Guendolen ’ at anchor 
S. end of lake (15 June, 1904 ; no. 577). 
206. NITZSCHIA LINEARIS, W. Sm. Brit. Diat. i. p. 39, t. 13. fig. 110. 
Var. TENUIS, Grun.—N. tenuis, W. Sm. 
Nyasa.—In swamp, Kota Kota (20 June, 1904 ; no. 18). 
Tanganyika.—In swamp, Mrumbi (27 Dec. 1904 ; no. 196). 
207. Митизснта Patra, (Kätz.) W. Sm. L e. ii. p. 89.—Synedra Рава, Kütz. 
Басі. (1844) t. 3. fig. 27, t. 4. fig. 2. 
Nyasa.—In swamp, Kota Kota (20 June, 1904 ; по. 18). On rocks, 
Nkata Bay (24 June, 1904 ; no. 23). In swamp, Karonga (2 July, 1904 ; 
no. 84). 
Victoria Nyanza.—In plankton, near Bukoba (21 Apr. 1905 ; no. 252). 
 Tanganyika.—On rocks, Niamkolo Harbour (7 Sept. 1904 ; no. 87). In 
plankton, near Mbete (28 Sept. 1904; no. 108). In swamp, Toa (10 Jan. 
1905 : no. 208). 
Var. DEBILIS, Van Heurck. 
Victoria Nyanza.—On rocks, Bukoba (17 Apr. 1905 ; no. 248). 
Var. TENUIROSTRIS, Van Heurek. 
Tanganyika.—In swamp, Toa (10 Jan. 1905 ; no. 208). 
268. NITZSCHIA nyassEnsis, O. Mall. т Engl. Bot. Jahrb. xxxvi. (1905) 
‚ 177, t. 2. figs. 5-9. 
Long. 380—430 ш; lat. ad med. (aspect. valv.) 3-2 д. (РІ. 4. figs. 7-9.) 
Nyasa.— [In plankton, off Vahambwera Point (24 June, 1904 ; no. 24) and 
off Karonga (1 July, 1904 ; по. 30). Also in swamp, Kambwelagoon near 
Karonga (27 June, 1904 : no. 29). 
Tanganyika.—In plankton, Niamkolo (July and Aug. 1904 ; nos. 36, 39, 
and 52), Kituta Bay (Aug. 1904 ; nos. 77 and 81), near Mbete (28 Sept. 
1904 ; поз. 105 and 109), Komba Bay (11 Oct. 1904; no. 135), Vua Harbour 
(29 Oct. 1904 ; no. 150), near Kalambo (5 Nov. 1904 ; no. 154), near Kirando 
(1 Dec. 1904 ; no. 175), Utinta (5 Dec. 1904 ; no. 181), and near Maswa 
(14 Jan. 1905 : по. 211). Also in Mtondwe Bay, among Alg% scraped from 
shells (2 Sept. 1904 ; no. 83). 
This Diatom occurred in prodigious quantity in the plankton of Tanganyika, 
more especially from July to September. Iam somewhat doubtful regarding 
its exact identification, as it seems to me to resemble so closely the slender 
and elongated species of Synedra. It undoubtedly agrees with Miiller’s 
м2 
— 
> 
