OF THE THIRD TANGANYIKA EXPEDITION. 167 
Forma cellulis curtis, polis mucronatis, ad formam apiculatam (= C.apiculata, 
W. Sm.) accedens. 
Tanganyika.—In plankton, near Kala (19 Nov. 1904 ; no. 170). 
Var. LATICEPs, O. Müll. in Engl. Bot. Jahrb. xxxiv. (1905) p. 22 cum fig. 2. 
Nyasa.—In plankton, Anchorage Вау (14 June, 1904 ; no. 10). 
281. CYMATOPLEURA Nyansa, sp. n. (РІ. 8. fig. 8.) 
C. magna et insignis ; cellula ut in visa aspectu valvulari in parte mediana 
angusta et subcylindrica, in partibus apicalibus valde inflatis subcircularibus, 
polis submamillatis ; costis ad margines laterales 7 in 10 р; cellula ut in 
visa aspectu cingulato ut in C. Solea. 
Long. 189-195 р; lat. in med. 20 ш; lat. max. (part. polar.) 56-58 p. 
Victoria Nyanza.—Not uncommon in the plankton, near Bukoba (April 1905; 
nos. 249 and 252). 
This species is distinct from C. Solea by reason of its curious dumbbell- 
shaped valves. The median part of the valve is relatively narrow, and the 
polar portions are almost circular in outline. 
Class MYXOPHYCEZE. 
Order HORMOGONEZE. 
Family STIGONEMACEZE. 
Genus NOSTOCHOPSIS, Wood. 
282. Nosrocuorsis Gorrzet, Schmidle, in Bot. Centralbl. Ixxxi. (1900) 
p. 417.—Myxoderma Goetzei, Schmidle, in Engl. Bot. Jahrb. xxx. (1902) 
p- 246, t. 4. figs. 2, 3. 
Crass. fil. prim. (cell. torulos.) 4—5 ш; crass. ram. (cell. суПпаг.) 2-3 ш; 
crass. heteroeyst. 575-675 р. 
Nyasa.—Taken in a shrimp-net in about 4 feet of water (15 June, 1904 ; 
no. 12). 
The plants occurred in free-floating gelatinous masses of irregular outline, 
reaching a diameter of several ems. The main portions of the primary 
flaments were more or less torulose, and the cells were of very variable 
shape. The lateral branches consisted of cylindrical cells, 21—4 times longer 
than the diameter, with slight constrictions between them. The apical cells 
were bluntly rounded. The heterocysts were invariably lateral, either sessile 
or stalked, the stalk consisting of one to three rounded cells. Each branch 
is attached to the side of one of the primary cells, from which it originally 
arose as а small lateral outgrowth. 
The specimens collected by Dr. Cunnington agreed very well with 
Schmidle’s description and figures, the plants he examined being collected in 
the vicinity of Nyasa in 1899. 
