Sixkurastrum xi. DESMiDiACE^f; (West). 361 



16. S. punctulatum Breb. in Ralfs,'Brit. Desm. 1.33, t. xxii. 

 f. 1 (1848); W. et G. S. West in Journ. Bot. 1897, p. 181. 



Forma 3-gona. 



PuNGo AxDOXGO. — In rivulis Praesidii (Casalalo) ; March 1857. 

 No. 105. 



Forma A-gona. 



HuiLLA. — In uliginosis editioribus prope Humpata, Empalanca et 

 LopoUo ; May 1860. No. 15. 



17. S. dilatatum Ehrenb. Infus. 143, t. x. f. 13 (1838); Ralfs, 

 Brit. Desm. 133, t. xxi. f. 8 (1848); W. et G. S. West, I.e. 



PuNGO Andgngo. — In rivulis Prsesidii (Casalale) ; March 1857. 

 No. 105. 



Var. insignis Racib. in E-osprawy Akad. Umiej. Krakow, 

 Wydzial. Mat.-przyr. ser. 2, t. ii. (vol. xxii.) 388, t. vii. f. 13 

 (1892); W. et. G. S. West, I.e. 



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



18. S. hexacerum Wittr. in Bih. t. K. Vet.-Akad. Handl. 

 Bd. 1. no. 1, 51 (1872); W. et G. S. West, I.e. Desmidium? 

 hexaceros Ehrenb. Abhandl. Akad. Wissenschaft., Berlin, 1833, 

 293 (1835); Infus. 141, t. x. f. 10 (1838). 



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



19. S. micron W. et G. S. West in Journ. B. M. S. 159, t, iv. 

 f. 50-51 (1896). 



Var. angolense W. et G. S. West in Journ. Bot. 1897, p. 181, 

 t. 368, f. 19. 



HuiLLA. — In paludibus exsiccandis ; April 1860. No. 176. 



20. S Gurgeliense Schmidle in Oestei-reich. Botan. Zeitschr. 64, 

 t. xvi. f. 23, 24 (1896). 



Var. tropicum W. et G. S. West in Jouini. Linn. Soc. 1897, p. 

 182, t. 368, f. 20. 



HriLLA. — In paludibus exsiccandis ; April 1860. No. 176. 



This may be a proper species, but only one example was met with 

 and, until further examples are obtained, it had better be regarded as 

 a variety of Schmidle's alpine species. 



21. S. elegantissimuni John.son in Bull. Tovr. Bot. Club, xxi. 

 290, t. 211, f. 16 (1894). 



Var. reductum W. et G. S. West in Journ. Bot. 1897, p. 182. 

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



22. S. cerastoides W. et G. S. West in Journ. Bot. 1897, p. 182, 

 t. 369, f. 13. 



HuiLL.v. — In uligino.sis editioribus prope Humpata, Empalanca et 

 LopoUo, plagas spongiosas unacum Eriocauloneis, Xyridibus et 

 Utriculariis constituens ; May 1860. No. 15. Etiam in paludibus 

 exsiccandis ; April 1860. No. 176- 



This species possesses in common with its nearest ally S. Cerastes 



