186 MESSRS. W. WEST AND G. S. WEST ON 
253. STAURASTRUM SUBGRACILLIMUM, West & G. S. West, in Trans. Linn. Soc., ser. 2, 
Bot. v. 1896, p. 263, t. 17. fig. 34. 
Forma processibus brevioribus, leviter curvatis. | Long. 15,4; lut. sine proc. 11:5 y, 
cum proc. 404; lat. isthm. 6 u. 
Hab. With the preceding species. 
The specimens observed from Ceylon differed chiefly from the N.-American ones in the 
shorter processes. 
254. STAURASTRUM SUBPARVULUM, sp. n. (Pl.22. fig. 7.) S. parvum, circiter 1l-plo 
longius quam latum (sine processibus), modice constrictum, sinu aperto; semicellulz 
subrectangulares, apicibus concavis, angulis inferioribus cum spina minuta, angulis 
superioribus in processus longos tenues subdivergentes minutissime nodulosos pro- 
ductis, apicibus processuum levissime dilatatis et minute tridenticulatis; a vertice 
visee late elliptieze, polis in processus longos subsigmoideos productis. 
Long. sine proc. 104; lat. sine proc. 9 u, cum proc. 51,4; lat. isthm. 4-2 nu crass. 7 u. 
Hab. Paddyfields, Heneratgodlia. 
This species is unquestionably nearest to S. parvulum, West & G. S. West (I. c. 
p. 268, t. 17. fig. 1), but differs in its much longer processes, which are outwardly 
curved, and also in the form of its vertical view. 
_ 255. STAURASTRUM COLUMBETOIDES, sp. n. (Pl. 22. figs. 8, 9.) S. parvum, circiter 12-plo 
longius quam latum (sine processibus), profunde constrictum, sinu sublineari ; semi- 
cellule late truncato-pyramidatee (ut in Cosmario nitidulo), angulis inferioribus sub- 
rotundatis, lateribus et apicibus subrectis, angulis superioribus in processus longis- 
simos tenuissimos valde divergentos flexuosos delicate nodulosos productis, apicibus 
processuum bifurcatis ; corpus semicellularum a vertice visum rotundo-rhomboideum, 
a latere visum rotundo-pyramidatum. 
Long. sine proc. 14:5—17 u, eum proc. 63-71:54; lat. sine proc. 13-14 u; lat. isthm. 
5-5'5u; crass. 13 u. 
Hab. Paddyfields, Heneratgodha. 
We know of nothing approaching this peculiar Staurastrum, with the body of a 
Cosmarium and the extraordinary diverging processes. 
256. STAURASTRUM EXCAVATUM, West & G. S. West, /. c. 1895, p. 78, t. 8. fig. 42. 
Long. 18:54; lat. sine proc. 11 4, cum proc. 53 4; lat. isthm. 424; crass. 677 m. 
Hab. With the preceding species. 
257. STAURASTRUM INDENTATUM, sp. n. (Pl. 22. figs. 10-12.) (=S. Pseudosebaldi, 
Wille, var. bicorne, Boldt, “ forma cum centrali parte apicis non inciso-aspera," 
W. B. Turn. in K. Sv. Vet.-Akad. Handl. xxv. 1893, no. 5, p. 123, t. 14. fig. 14) 
S. subparvum, circiter 11-plo latius quam longum (eum processibus), subprofunde 
constrictum ; semicellule obeuneatze, subinflate, ad basin eum denticulo utrobique, 
marginibus lateralibus verrucis emarginatis 2 ornatis, angulis superioribus in 
processus lengos leviter et gracillime incurvatos productis, marginibus processuum 
