The Freshwater Al-jcu of Africa. 589 



Var. saxonica, Rabenh. ; Cleve, op. cit, p. 123. (Syn. : N.saxonica, 

 Rabenh. ; N. crassmervia, Breb.) 



Samples 1, 7, 8, 9, 10, 43. 



Long., 48-63 (i; lat., 12-15 p. 



2. Navicula (Frustulia) vulgaris, Thw. ; Cleve, op. »■//., p. L22. 

 (Syn.: Vanheurckia vulgaris (Thw.), Van Heurck, op. c#., p. 112, PI. 

 XVII, fig. 6 ; Colletonema vulgaris, Thw.) 



Sample 41. 



Section NAVICULAR MESOLEIAE Cleve. 



1. Navicula pupula, Kuetz. ; Cleve, op. cit., p. 131; Van Heurck, 

 op. cit., p. 106, PL XIII, figs. 15, 16. 



Vav. subcapitals, Husteclt ; v. Schoenfeldt, Bacillariales, in A. 

 Pascher, Snesswasserflora Deutschlands, Osterreichs, etc., x, 1913, 

 p. 79 (Fig. 40, e). 



Samples 4, 6. 



The type has been recorded from Smith Africa by Gr. S. W est. 



Section NAVICULAE MINUSCULAE Cleve. 



1. Navicula muralis, Grim. ; Cleve, op. cit., ii, p. 3. 

 Sample 41 (very rare). 



Section NAVICULAE LLNEOLATAE Cleve. 



1. Navicula cincta, Ehrenb. ; Cleve, op. cit.. p. 16; Van Heurck, 

 op. cit., p. 82, PL VII, figs. 13, 14. 



Samples 4, 5, 6, 25, 43. 



A not uncommon form. Long., 27-36 /x ; lat., 6-7 /', 



2. Navicula cryptocephala, Kuetz.; Cleve, op. cit., p. 14; Van 

 Heurck, op. cit, p. 84, PL VIII, figs. 1, 5. 



Samples 4, 25, 26, 31, 32, 33, 36, 43, 48. 

 Long., 22-35 /x ; lat., 5-7 - 5 /x. 



Recorded from Holle River, Calvinia Division ; Gransfontein, Ceres 

 Division ; and Little Nauuu jualand by Gf. S. West. 



3. Navicula rhynchocephala, Kuetz.; Cleve, op. cit., p. 15; Van 

 Heurck, op. cit., p. 84, PL VII, fig. 31. 



Samples 4, 6. 



Previously recorded by Wide from South Africa. 



4. Navicula r<i>iinsii . Kuetz.; Cleve, op. cit., \>. L7; Van Eeurck, 

 op. cit., }>. 83, PL VII, fig. -2". (Syn.: N. acuta, W. Smith.) 



