THE YAN УКАМ RESERVOIR, VICTORIA. $7 
14 & 15. S. corniculatum var. spinigerum ; 16 & 17. 5. mucronatum var. delica- 
tulum; 18. S. sevangulare; 19. Melosira granulata; 20. Cosmarium pseudo- 
protuberans var. angustius; 21. Closteriopsis longissima. 
gs, 22 & 23. Micrasterias Hardyi; 24. Staurastrum assurgens var. victoriense; 25. S 
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leptacanthum ; 26, 5. dejectum ; 27, Cosmarium pseudoprotuberans var. angustius ; 
28, C. Capitulum var. australe; 29. Ankistrodesmus falcatus; 30. Melosira 
granulata. 
3] A 32. Micrasterias Hardyt; 83. Damaged semicell of Cosmarium achondroides ; 
54. С. Hardyi; 35. C. Capitulum var. australe; Зб & 37. C. tortum forma 
trigona: 38. Staurastrum corniculatum; 39. 5. assurgens var, victoriense ; 
40. S. paradoxum var. longipes; 41. №. cuspidatum: 42. Old carapace of 
Bosmina, with quantities of decaying organic matter attached. 
Note.—The dark, ill-defined patches in the March and April plankton consist of irregular 
masses of decaying organic matter. 
PLATE 2. 
Fig, 1. Mougeotia victoriensis, sp. п. x 500. Conjugating filaments showing two spores 
each surrounded by a wide mucous coat to whieh are attached numerous small 
particles of mineral matter. 
Figs. 2-3. Zygnema spontaneum, Nordst. x 500. In fig. 3 one zygospore (z) is shown and 
two aplanospores («pl.). 
4-5. Mougeotia subcrassa, sp. п. 4, X 200; 5, spore with portions of walls of attached 
cells, x 500. 
6-11. Debarya Hardyi, sp. п. 6, x 500; early stage of conjugation, just after forma- 
tion of conjugating-tube ; 7-9, х 1000, extremities of emptying gametangia to 
show the internal thickening which is gradually laid down until they become solid. 
10 & 11, two adult zvgospores, x1500. 
12-14. Ulothrir idiospora, sp. п. 12 © 13, two filaments showing vegetative cells and 
adult akinetes (ap/.), 500. х chl, chloroplast; py., pyrenoid. 14, akinete to show 
` scrobiculation of wall, x 1000. 
15. Ceratium Hirundinella, О. F. Müll. x 200. A form from the plankton of the 
Toorourong Reservoir showing an inward curvature of the third antapical horn (a). 
PLATE 3. 
Figs, 1-2. Pleurotenium mamillatum, G. S. West. 1, x 520; 2, x 430, 
3. Spherozosma Wallichii, Jacobs., forma australis. х 840. 
4-5. Triploceras grecile, Bail, var. robustum, var. п. X 500. 5, side view of another 
apex. 
6-7. Triploceras gracile, Bail, var. aculeatum, Nordst., forma. х 500. 7, side view 
of apical region. 
8-10. Triploceras gracile, Bail, var. denticulatum, (Playfeir) nob. x 500. Fig. 9 
shows side view of apical region. 
11. Staurastrum unicorne, W. В. Turn, var. nodiferum, (W. В. Тат.) W. & G. 
S. West. А form, x 840. 
12. Staurastrum neglectum, sp. п. a and b, x 500: 0, x 840. 
13. Nuvicula bicapitata, Lagerstedt. х 840. 
14. Eunotia crispula, sp. n. X 500. 
15-16. Rhizosolenia morsa, W. & С. б. West. x 840. 
17. Gyrosigma elongatum, (W. Sm.) nob, var.? x 500, 
