— 162 — 
13. S. gracilis Ktitz. Spec. Algar. 1849, p. 438; Rabenh. Flor. Europ. 
Algar. Ill, p. 237; Petit Spirog. de Paris, 1880, p. 15, t. Ill, f.7—3. 
Forma cellulis paullo longioribus. 
Crass. cell. veget. 17,5192; crass. cell. fruct. 27 4; long. zygosp. 
54—63 u; lat. zygosp. 24--25 p. 
In stagnant water in riverbed. 
Area: Europe and N, America. Abyssinia (var. abyssinica Lagerh.). 
Fam. Desmidiacee. 
Gonatozygon De Bary. 
14. G. Ralfsii De Bary Conj. 1858, p. 76, t.IV, f. 23. 
Long. 163—220 y; lat. 11,6--13,5 yw. 
In stagnant water amongst Spirogyra decimina var. 
Area: N. and S. America, W. Indies, Europe, Siberia, China, India, Ceylon. 
Sumatra, E. arid W. Africa, Australia. 
15. @. Kinahani Rabenh. Flor. Europ. Algar. Ill, 1868, p. 156. 
Leptocystinema Kinahani Arch. 1858. 
Var. tropicum West & G.S. West, n. var. (Tab. nostr. II, fig. 2). 
Var. cellulis multo crassioribus. 
Long. 336 4; lat. 20—23 pw. 
In stagnant water, amongst the preceding species. 
Area of type: Europe. 
Cylindrocystis Menegh. 
16. (€. Brébissonii Menegh. 1838; De Bary Conj. 1858, p. 35, 46, 
74, t. VI, f. E1—22. Penium Brébissonii Ralfs 1848. 
Long. 53—78 yp; lat. 15—16,5 p. 
In stagnant water in riverbed. 
Area: Ubiquitous. 
17. ©. subpyramidata West & G. 5S. West, n. sp. (Tab. nostr. Il, 
fig. 8—11). 
C. parva, pene duplo longior quam lata; cellulis ellipticis, 
leviter et subgradatim constrictis ad medium; semicellulis ovato- 
pyramidatis, polis rotundo-subtruncatis; membrana glabra achroa: 
a vertice visis circulavibus; pyrenoidibus singulis, magnis. Zygospore 
nigrescentes, oblongo-rectangulares angulis rotundatis, a latere visx 
ellipticee; in medio laterum membrana valde et subirregularite: 
incrassata. 
Long. 27—28 ; lat. 15—16 1; lat. constrict. 14,5 1; long. zygosp 
32,5—34 w; lat. zygosp. 23—25 w; crass. zygosp. 20 pw. 
