364 XIV. PALMELLACE^ (West). [Pedidstrum 



3. PEDIASTRUM Meyen (1829). 



1. P. Tetras Ralfs in Ann. Nat. Hist. xiv. 469, t. 12, f. 4 (1844) ; 

 W. et G. S. West, I.e. 



Micrasterias Tetras Elirenb. (1838). 



HuiLLA. — In paludibus exsiccandis ; April 1860. Ifo. 176. Inter 

 Utriculai-iam, Morro de LopoUo ; April 1860. No. 179. 



LiBONGO. — Ad margines flum. Lifune ; Sept. 1858. No. 204. 



4. OPHIOCYTIUM Niig. (1849). 



1. 0. majus Niig. Gatt. einz. Alg. 89, t. iv. A, fig. 2 (1849); 

 W. et G. S. West, I.e. 



PuNGo Andoxgo. — In stagnis prope Anbilla (Condo) ; March 1857. 

 No. 177. 



2. 0. parvulum A. Br. Alg. Unicell. 55 (1855); W. et G. S. 

 West, I.e. 



Broehidium jxirvuhmi Perty. 



HuiLLA. — In uliginosis editioribus prope Humpata, Empalanca et 

 Lopollo ; May 1860. No. 15. 



PuNGO AxDoxcio. — In stagnis prope Anbilla (Condo) ; March 1857. 

 No. 177. 



5. SCENEDESMUS Meyen (1829). 



1. S. denticulatus Lagerh. in Ofv. Kongl. Vet.-Akad. Forhandl. 

 1882, no. 2, 61, t. ii. f. 13-16. 



Var. linearis Hansg. in Archiv. Naturwiss. Landesdurchf. 

 Bohm. Bd. 6, no. 268 (1888); W. et G. S. West in Journ. Bot. 

 1897, p. 237. 



LiBONGo. — Ad margines flum. Lifune ; Sept. 1858. No. 204. 



6. TETRAEDRON Kiitz. (1845). 



1. T. minimum Hansg. in Hedwigia, 1888, 131 ; W. et G. S. 

 West, I.e. 



Polyedrium minimum A. Br. in Babenh, Fl. Europ. Alg. iii. 62. 



From, the references given under the name T. minimum in his 

 .paper in " Hedwigia " it would appear that Hansgirg was under 

 the erroneous impi-ession that Braun described this plant in Rabh. 

 Fl. Europ. Alg. as a Tetraedroii. 



LiBOXGO. — Ad margines flum. Lifune ; Sept. 1858. No. 204. 



2. T. tropicum W. et G. S. West in Journ. Bot. 1897, p. 237. 

 LiBOXGo. — Ad margines flum. Lifune ; Sept. 1858. No. 204. 



This should be compared with T. retk-ulafum (Reinsch) Hansg. : 

 in the latter species the membrane is not nearly so thick, and the 

 scrobiculations are so large that the superficial part of the membrane 

 only consists of a fine reticulation. 



3. T. tetragonum Hansg. I.e. (1888). 



Polyedrium tetragonum ISTiig. Gatt. einz. Alg. 84, t. iv. B, 

 fig. 2 (1849). 



Var. inerme (Wille in Bihang t. K. Sv. Vet.-Akad. Handl. Bd. 

 8, no. 18 (1884), 12, t. i. f. 25) ; W. et G. S. West, I.e. 



