The Freshwater Algae of Africa 555 



these views closely resembling those shown by Messrs. West (cf. 

 Fig. 28, h). 



9. Cosmarium meneghinii, Brcb. ; W. A <i. S. West, op. cit., iii, L908, 

 p. 90, PI. LXXII, figs. 29 32, 



Forma marginibus lateralibus inferioribus leviter divergentibus ; 

 aliocpii typo el non var. nano Wille similis est. Long., 24 \>- ; lat., 

 15 // ; lat. isth., 5 //. 



Sample 19 ( rare ). 



In. Cosmariv/m rectangulare, Grun. ; W. & G. S. West, op. cit., iii, 

 1908, p. 54, PL LXX, figs. 1. 2. 



Forma apicibus interdum leviter retusis, membrana laevi. Long., 

 20 fi ; lat. 15 //. ; lat. isthm., 3-4-5 fi (Fig. 28, c). 



Sample 31 (rare). 



A small form, which appears rather as an extreme condition of the 

 forms of G. perpusillum, West, shown in Fig. 28, e,f. Messrs. Wesl 

 (Alg. Centr. Afr., Journ. Bot., xxv, 1896, p. 379, Tab. 361, fig. 14) 

 have described a var. africanum of C. rectangulare, which is, however, 

 proportionally longer. 



11. Cosmariutn laeve, Rabenhorst, FI. Europ. Alg., iii, 1868, 

 p. 161 ; W. A G. S. West, op. cit, iii. 1908, p. '•'!♦, PL LXXIII, 

 figs. 8 19. 



Forma membrana laevi. Long., 18-30 /x, ; lat., 15-21 fi ; lat. isthm.. 

 3'5-5 //. : crass.. 10 fx. 



Samples 14, 52, 54, 55. 



Var. septentrionale, Wille, Ferskvandsalg. Novaja Semlja, etc., 

 Ofvers. K. Vet.-Ak. FoerhandL, 1870, No. 5, p. 43, Tab. XII, fig. 34. 

 W. & G. S. West, loc. cit, p. 102, PL LXXIII, tigs. 212-25. 



Sample 52. 



The type lias been recorded from Little Namaqualand by G. S. 



West. 



12. Cosmariumpunctulatum,Bveb.; W. & G. S. West, op. cit, iii, 

 1908, p. 206, PL LXXXIV, figs. 13. 14, and PL CII,fig. 22. 



Samples 2 (rare), 7, 10 (rare), 29 (rare). 



The abundant individuals in sample 7 were veiy typical ; long., 

 32-36 /y; lat., 28 30 /a; lat. isthm., 8 10/x; crass., 17-18 ju,. Somehad 

 a slightly concave apex. In many cases the end-view showed a slight 

 median non-granulated inflation. This species has Keen recorded by 

 Reinsch from the < 'ape. 



V ar ■; subpunctidatum (Nordst.), Boergesen ; W. ■& G. S. West, ioe. 



