542 



Annals of the South African Museum. 



Cellulis exacte cylindricis, se<l plus minus evidenter curvatis, polis 

 rotundatis. Long., 48-72 /x ; lat., 15-17 p.. 

 Samples 8, 9, 50. 



-p m 20. A. Cylindrocystis crassa, De Bary, from sample 50, cf. text, 



p. 541. B. Netrium oblongum (De Bary), Luetk., var. cylindricum, W. A: 

 (jr. S. West, forma curvata, n. f. C. Cylindrocystis ornata, n. sp. 

 I) Penium phijmatos-porum, Nordst., forma. and D x 750. Magni- 

 fication of A and -B shown by the scale. 



[2) DESMIDIA.CEAE. 



Genus PENIUM Bbebisson. 



1. Penium margaritaceum ( Ehrenb.), Breb. ; W. & Gr. S. West, 

 of. cit., i, 1904, p. 83, PI. VIII, figs. 32-35. 



Var. irregularius, W. & Gr. S. West, Freshw. Alg. Orkneys and 

 Shetlands, Trans. & Proc. Bot. Soc. Edinburgh, xxiii. 1905, pp. 14, 15, 

 fig. 23. 



Sample 4. 



Long, cell., 90 /a; lat.. 18/'. The cell-membrane is colourless, the 



