65 DR. С. Я. WEST ON THE ALGÆ OF 
43. STAURASTRUM LÆVISPINUM, Biss. in Journ. Roy. Mier, Soc. (1884) 
р. 195, t. 5. fig. 5. 
Var. SUBBRACHIATUM, G. 5. West, in Victorian Naturalist, xxii. (1905) 
р. 72; in Journ. Bot, xliii. (1905) p. 255. 
Var. processibus angustioribus basin versus et хере emarginato-furcatos 
ad apices. 
Long. s. proc. 17-185 м, cum proc. 30-35 p; lat. 11-12 и, c, proc. 
30—32 н; lat, isthm. 65-7 р. (Pl. 5. fig. 10.) 
Hab. Yan Yean Reservoir, in the plankton (Mar. and Apr. 1905). 
This variety is distinguished by the greater differentiation which exists 
between the processes and the body of the semicells. Some or all of these 
processes are often emarginate at the apex. 
It should be compared with S. levispinum forma sydneyensis, Racib. (in 
Rospraw Wydz. matem.-przyr. Akad. Umiej. Krakow. xxii. (1892) p. 379 
t. 7. fig. 10). 
44. STAURASTRUM SENARIUM, (Zhrenb.) Ralfs, Brit. Desm. 1848, p. 216 ; 
Wolle, Desm. U. S. 1884, p. 147, t. 52. fig. 1; W. B. Turner, т К. Se. 
Vet.-Akad. Handl. Bd. 25, no. 5 (1893) p. 119, t. 15. fig. 13.—8. pseudo- 
pisciforme, JZiehl. у Gutw., var. denticulatum, Létkem. in Ann. k. k. Nat. 
Hofmus. Wien, Bd. ху. (1900) р. 124, t. 6. figs. 37, 38. 
Long. 42-46 u ; lat. с. proc. 46-58 ш; lat. isthm. 11-154. (РІ. 6. fig. 13.) 
Hab. Yan Yean Reservoir, in the plankton (Mar.-May, 1905) and at the 
weedy margins (Mar.-July, 1905). 
Much doubt prevails concerning the exact identity of Staurastrum senarium, 
although it is generally accepted as a species closely akin to S. furcatum, 
Ehrenb., but provided with twelve accessory processes in place of the six 
which are so characteristic of the latter species. The Australian plants 
reached their maximum abundance in April. Six of the accessory processes 
were in the same plane as the three angular processes, and six were apical. 
The angles of the semicells were gradually produced into a slightly divergent 
process which was either quite smooth or furnished with a ring of four small 
denticulations. The presenee of these denticulations is a feature of little 
importance, as they may be present on the angular processes of one semicell, 
but absent from those of the other. 
45. STAURASTRUM PATENS, W. B. Turn. in К. Sr. Vet.- Akad. Handl. 
Bd. 25, no. 5 (1893) р. 108, t. 14. fig. 21. | 
Var. PLANCTONICUM, (7. S. West, т Victorian Naturalist, xxii. (1905) р. 135. 
in Journ. Bot. xlii. (1905) p. 254.—S. patens f. australica, Playfair, in 
Proc. Linn, Soc. N. S. Wales, xxxii. pt. 1 (1907), p. 189, t. 5. fig. 9. 
Var. paullo minor, angulis leviter productis trispinatis; semicellulæ a 
vertice vise lateribus subrectis, angulis leviter productis et trispinatis. 
