THE FRESHWATER ALGÆ OF CEYLON. 187 
minute nodulosis, apicibus processuum distincte sed leviter bifureatis, apicibus semi- 
cellularum leviter convexis (vel subrectis) cum  verrucis depressis denticulatis 
ornatis, ad marginem superiorem in parte proxima processuum verrucis emarginatis 
1-2; a vertice vise subglobos:w, lateribus valde incrassatis, polis in processus longos 
rectos undulato-nodulosos productis, cum serie verrucarum bi- vel tridenticularum 
intra marginem lateralem unumquemque. 
Long. 34-394; lat. eum proc. 52-76 4; lat. isthm. 6-8 u; crass. 17 u. 
Hab. Paddyfields, Heneratgodha. 
This species was observed in abundance, and is undoubtedly identical with the figure 
given by Turner of S. Pseudosebaldi, var. bicorne, forma. Turner’s figure, which is copied 
from one of G. C. Wallich's drawings under a magnification of 330 diameters, lacks 
much detail; but the proportion, the curvature of the processes, and the general outline 
of the plant are such as to render positive its complete identity with S. imdentatum. 
Turner describes the central part of the apex as “ non inciso-aspera," and this portion of 
the front view of the plant has been represented by Wallich as a straight line. This we 
can quite imagine under a magnification of 330 diameters, as it is not until the plant is 
examined under a magnification of at least 500 diameters that the nature of the apex is 
apparent. It is then seen to consist of a series of flattened warts ornamented with 
minute teeth. These warts are seen much better in the vertical view, and are represented 
to a certain extent in the tilted view given by Wallich (cf. Turner, in K. Sv. Vet.-Akad. 
Handl. xxv. 1893, no. 5, t. 14. fig. 14 b). 
S. indentatum possesses very little in common with S. Pseudosebaldi, var. bicorne, 
Boldt (in Ofvers. K. Vet.-Akad. Fórh. 1885, no. 2, p. 117, t. 6. fig. 36); the basal 
portion of the semicells is much narrower and ornamented with warts, the apex exhibits 
in front view quite a different character, and the graceful curvature of the processes 
causes the general aspect of the Staurastrum to appear totally different. 
258. STAURASTRUM SUBSALTANS, sp. n. (Pl.22.fig. 15.) S. subparvum, circiter 13-plo 
latius quam longum (cum processibus), profunde constrictum; semicellule ob- 
cuneatz, marginibus lateralibus cum verrucis truncato-emarginatis magnis 2 ornatis, 
angulis superioribus in processus longos subrectos dentato-nodulosos horizontaliter 
dispositos productis, apicibus processuum bifurcatis, apicibus semicellularum elevatis 
et subtruncatis cum spina subhorizontaliter dispositis ad elevationem utrobique; a 
vertice visse rhomboideo-globoss, lateribus incrassatis, polis in processus longos 
rectos subundulatos productis, ad basin processus uniuscujusque intra marginem cum 
spinis distantibus subparallelis binis. 
Long. 34; lat. eum proc. 52-56 u; lat. isthm. 6u; crass. 144. 
Hab. Paddyfields, Heneratgodha. 
This species is most closely allied to S. saltans, Joshua, from which it is chiefly dis- 
tinguished by the mueh smaller and narrower body, and by the prominent subtruncate 
warts on the lateral margins. The processes are almost straight and horizontal, and less 
markedly dentate than those of S. saltans; moreover, the pair of spines on each side of 
the apical elevation are shorter and are attached directly tojthe elevation in S. subsaltans, 
SECOND SERIES.—BOTANY, VOL. VI. 2D 
