The Freshwater Algae of Africa. 585 



(2) COSCINODISCACEAE. 



Genus CYCLOTELLA Kuetzing. 



1. Cyclotella operculata, Kuetz.; Van Heurck, op. cit., p. 214, PL 

 XCIII, figs. 22-28. 

 Samples 25, 31, 33, 48. 



(b) PENNATAE. 

 A. FRAGILARIOIDEAE. 



(4) FRAGILARIACEAE. 



Genus SYNEDRA Ehrenberg. 



1. Synedra pulchella, Kuetz.; Van Heurck. op. cit., p. 149, PI. XL, 

 figs. 28, 29. 



Samples 21, 24 (in both cases on Oedogoniwm sp.), 30a, 31, 33 (on 

 Cladophora glomerata, etc.), 54. 



2. Sytiedra ulna (Nitzsch), Ehrenb. ; Van Heurck, op. cit., p. 150, 

 PL XXXVIII, fig. 7. 



Samples 25, 29, 29a, 31, 32, 33, 52, 54. 



Previously recorded from South Africa by Wille, and by G. S. West 

 from Holle River, Calvinia Division ; Gansfontein, Ceres Division, and 

 Little Namaqualand. 



3. Synedra acus (Kuetz.), Grun. ; Van Heurck, op. cit.. p. 151, PL 

 XXXIX, fig. 4. 



Samples 14, 28, 32, 52-55. 



Previously recorded by Wille from South Africa ; by G. S. West 

 from Little Namaqualand. 



4. Synedra radians (Kuetz.), Grun.; Van Heurck, op. cit., p. 151, 

 PL XXXIX, fig. 11. 



Samples 31 and 33 (on Cladophora glomerata). 



(5) EUNOTIACEAE. 



Genus EUNOTIA Ehrenberg. 

 ]. Eunotia diodan, Ehrenb.; Rabeuhorst, PL Europ. Alg., i, 1864, 

 p. 69, tig. Hi ; Van Heurck, op. cit., PL XXXIII, fig. 6. 

 Sample 10 (rather rare). 

 Long., 84/x; lat., 15-16//. 



