THE YAN YEAN RESERVOIR, VICTORIA, 67 
Dot. Gard. Caleutta, vi. (1907) p. 215, t. 16. fig. 1), which is known from 
Durma, but differs in the more elongated processes, each of which is con- 
stricted at the base, and in the proportionately smaller body of the semicells. 
In all forms of. Staurastrum levispinwn the processes gradually merge into 
the body of the semicell from a dilated base, whereas in 5. digitatum, ах in 
№. virtoriense, the processes are narrowed at the base and attached at definite 
points to the body of the semicell. 
The cell-wall is very thin, and the processes are hollow, a lobe ot the 
chloroplast passing into each process and extending almost to its apex. 
42. STAURASTRUM VICTORIENSE, sp. n. (РІ. 5. figs. 18-15.)—8. nudi- 
brachiatum, Borge, rar. victoriense, G. 5. West, in Victorian Naturalist, 
xxii. (1905) p. 72 ; in Journ. Dot. xliii. (1905) p. 255. 
^. mediocre, circiter li-plo latius quam longum (eum processibus), 
levissime. constrictum, sinu minimo vix conspicuo; зепиееПа subhemi- 
sphierico-globose, apice valde convexo (non depresso in parte mediana), 
‘corona processuum longorum leviter sursum divergentium 10-11 præditæ ; 
processibus rectis glabrisque, ad basin leviter constrictis et apicem versus 
gradatim attenuatis, apicibus processuum integris et obtuse conicis; a vertice 
visæ circulares, processibus glabris 10-11-radiatis ; chromatophoris ut in 
S. nudibrachiato ; membrana corporis subtiliter et irregulariter punctata, 
membrana processuum tenuiore et glabra. 
Long. s. proc. 45-46 ш; lat. sine proc. 35-305 p, c. proc. 79-96 ш; lat. 
isthm. 31 ш; crass. proc. 48-38 u; long. proc. 25-34 д. 
Hab. Yan Yean Reservoir, in the plankton (somewhat scarce throughout 
the entire year) and at the weedy margins (April-July, 1905 ; common in 
June and July). 
This curious species stands nearest to $5. audibrachiatum, Borge (т 
Arkiv Botan. К. Sv. Vet.-Akad. Bd. i. (1903) p. 109, t. 4. fig. 20), 
a Desmid recently described from Brazil; but as the characters of the 
Victorian plant are remarkably constant, and it eun be so easily distinguished 
from the Brazilian plant, I have thought it advisable to place it as a distinct 
species. 
The Australian species differs from the Brazilian one in the proportionately 
longer body of the cells, the slighter constriction, the narrower processes 
with entire apices, and in the greater number of processes on each semicell. 
No specimens were observed with any trace of teeth at the apices of the 
processes. The walls of the processes are much thinner than those of the 
body of the Staurastrum, and are perfectly smooth, whereas the rounded 
semicells are distinctly punctate, Each process is slightly constricted at the 
base, the. widest part being about one-third the length from the base. АП 
the specimens seen were either 10- or 11-radiate in vertical view. 
Compare also with S. subnudibrachiatum, W. & G. 5. West. 
F2 
