70 DR. С. $. WEST ON THE ALG OF 
Hab, Ottelia Creek, Yan Yean Reservoir, in pools (3 Sept. 1907). 
Neveral zygospores of this species were observed, and they were of a type 
most unusual in the genus Staurastrum. They were considerably flattened 
or compressed, being oblong in the side view, but having a circular outline 
in the front view with 10-12 prominent marginal undulations. These 
undulations were not caused by wart-like elevations but by ridges extending 
from one flattened side to the other. 
Wittrock has described a similar zygospore from Oland which he referred 
to S. striolatum var. oelandicum (vide Wittr. in Bih. till К. Sv. Vet.-Akad. 
Handl. Bd. i. no. 1 (1872) p. 52), but I can see no essential differences 
between Wittrock's variety and typical ©, striolatum. 
The zygospore of S. dilatatum, as described by Messrs. Roy and Bissett, 
is of а similar nature to that of S. striolatum, but, according to Ralfs, that 
of S. alternans is globular and furnished with forked spines. 
48. STAURASTRUM NEGLECTUM, sp. п. (РІ. 3. fig. 12.) S. tricorne, (Dri?.) 
Meneyh. var. B, Ralfs, Brit. Desm. (1848) р. 134, t. 34. figs. 8 b, с, d. 
S. parvum, 14-14-plo latius quam longum (cum processibus), minutissime 
(vix conspicue) constrictum ; semicellulæ parte basali breviter cylindrica, 
parte superiore incudiformi apice convexo, angulis in processus attenuatos 
minute denticulatos horizontaliter dispositos productis; a vertice visæ tri- 
angulares, lateribus corporis parvæ concavis, angulis in processus attenuatos 
sublongos rectus vel leviter curvatos productis ; processibus eum annulis 
dentieulorum minutorum 6-7 præditis, apices versus leviter dilatatis et 
apicibus tridenticulatis ; cellule plerumque tortæ, nonnunquam processibus 
alterius semicellulæ eum iis alterius alternantibus. 
Long. 28°5—26 ш; lat. c. proc. 32-35 ш; lat. med. cell. 6:5-7 p. 
Hab. Yan Yean Reservoir, among weeds at the margin (Jan. 1906), and 
in pool in the catchment area (Sept. 1907). 
This species differs from ©. hevacerum, (Ehrenb.) Wittr. (=S. tricorne, 
as described and figured by Ralfs), in the smaller body of the semicells, the 
cylindrical median part of the cells, with the faintest indication of a con- 
striction, and in the more elongate processes. The latter are also much more 
elegant and are dilated towards the extremities. Каі figure] the zygospores 
of both S. heracerum and 5. neglectum (=S. tricorne, var. В, Ralfs), and 
that of the latter is distinguished by the repeated furcation of the extremities 
of the spines (vide Ralfs, Brit. Desm. t. 84. fig. 8 d). 
5. neglectum is widely distributed, although rare, in the British Islands, 
and I have also examined specimens from Maine in the United States. 
49. STAURASTRUM BIBRACHIATUM, Reinsch, Contrib. Aly. et Fung. (1875) 
p. 85, t. 16. fig. 2. 
Var. CYMATIUM, W. у GŒ. S. West, in Trans. Linn. Soc. ser. 2, Bot. v. 
(1895) p. 74, t. 8. fig. 25, 
