THE FRESHWATER ALGÆ OF CEYLON. 181 
Var. TRIFURCATUM, West & G. S. West, * Freshw. Ailg. Madag, in Trans, Linn. Soc., 
ser. 2, Bot. v. 1895, p. 80, t. 9. fig. 8. 
Long. sine proc. 36 w, cum proc. 545; lat. sine proc. 27 w, cum proc. 50 w; lat. isthm. 
9'5 w. (Pl 21. fig. 27.) 
Hab. Paddyfields, Heneratgodha. 
The specimens observed were somewhat smaller than the examples from Madagascar ; 
most of them possessed nine processes in the lower whorl, but one individual was observed 
in which one semicell possessed nine processes in the lower whorl and the other semicell 
only three (cf. Pl. 21. fig. 27). Thus the extremes of variation (for this species) in the 
number of the processes were present in the same specimen. 
Var. INSIGNE, var. n. (Pl. 21. fig. 28.) Var. cellulis multe majoribus, processibus 18 
(inferioribus 9 et superioribus 9) longioribus et apicibus profundissime trifurcatis. 
Long. sine proc. 87, cum proc. 158 w; lat. sine proc. 57 w, cum proc. 1295; lat. 
isthm. 23 w. 
Hab. Paddyfield between Kosgoda and Urahaighasmahendai. 
This is much the largest of the varieties of S. tohopekaligense, and is distinguished by 
its long deeply trifureate processes. The specimen observed possessed nine processes in 
each whorl; but this may not be a definite character, as we have shown that the number 
of processes in each whorl varies considerably in varieties of this species. 
297. STAURASTRUM SEXANGULARE, Rabenh. Krypt. Flor. Sachs. 1863, p. 621; Lundell. in 
Nov. Act. R. Soc. Scient. Upsala, ser. 3, viii. 1871, p. 71, t. 4. fig. 9. ` Didymo- 
cladon sexangularis, Buln. in Hedwig. i. 1861, p. 51, t. 9 a. fig. 1 
Forma processibus basalibus subelongatis attenuatis et inflexioribus, denticulis nume- 
rosioribus et acutioribus. Long. sine proc. 364, cum proc. 54-584; lat. cum proc. 
67 w; lat. isthm. 10:5 œ. (PI. 21. fig. 34.) 
Hab. Paddyfields, Heneratgodha. 
Var. sUBGLABRUM, var. n. (Pl. 21. fig. 35.) Var. processibus inferioribus sursum curvatis, 
marginibus superioribus glabris, marginibus inferioribus cum denticulis binis; 
processibus superioribus brevioribus et glabris. 
Long. sine proc. 38:5 w, cum proc. 48w; lat. sine proc. 30w, cum proc. 62 w; lat. 
isthm. 9:5 p. 
Hab. Paddyfields, Heneratgodha. 
238. STAURASTRUM ZONATUM, Borg. 'Desm. Brasil, in Vidensk. Medd. naturh. Foren. 
Kjóbenhavn, 1890, p. 46, t. 5. fig. 48. 
Var. CEYLANICUM, var. n. (Pl 21. figs. 31, 32.) Var. semicellulis nonnunquam longior- 
` ibus subrectangularibusque, apicibus subdepressis; margine inferiore processuum 
trinoduloso, apicibus processuuin tridentieulatis ; à vertice visis 6-radiatis, pro- 
cessibus trinodulosis utrobique, in centro annulo denticulorum singulorum 6 
iustructo. 
202 
