296 8 
p. 323; Pl. f. the S. Atlantic and the S. Indian Ocean p. 932; Pl. f. the 
Indian Ocean and the Malay Archip. p. 21. 
Q(rr) — 6(r). 
Area: Eastern and Northern Atlantic Ocean, Antarctic Ocean, South Indian 
Ocean at 42°—45° 5S. and 3° W. to 48° E. 
20. D. mediterraneus Perag., Monogr. Rhiz. p.104, Pl. 1, f. 8, 9; 
Schréder, Neapel p. 24; Cleve, Pl. f. the S. Atl. and S. Ind. Ocean p. 932; 
Pl. f. the Red Sea, Ofv. af K. Sv. Vetensk. Akad. Férhandl. 1900, No. 9 
[1901], p. 1033; Atl. Plankt. Organisms p. 324; Pl. f. the Indian Ocean 
and the Malay Archip. p. 21; Ostenfeld, Vid. Medd. Nath. For. Kjabenhavn, 
1898, p. 428; Ostenfeld & Schmidt, Pl. f. the Red Sea, etc. p. 157. 
Q(+) — 4&(rr) — S(rr) — 6(4+) — 7 (rr) — 10 (tr). 
Area: Temperate North Atlantic Ocean, Tropical Atlantic at Puerto Ca- 
bello, Southern Atlantic and Indian Ocean at 42°—44° S. and 3° W.—48° E., 
Mediterranean, Red Sea, Gulf of Aden, Gulf of Bengal, Malay Archipelago. 
Lauderiopsis Ostf. 
91, I. costata Ostf. in Ostenfeld & Schmidt, Pl. f. the Red Sea, etec., 
p- 158, f. 10. 
This genus forms a connecting link between Lauderia, Dactyliosolen 
and Guinardia. 
2(r) — 6(4). 
Area: Red Sea. 
Guinardia Perag. 
29. G, flaccida (Castr.) Perag., Monogr. Rhiz. p. 107, Pl. 1, f.83—5; 
de Wildeman, |. c. p. 122; Schréder, Neapel, p. 24; Ostenfeld & Schmidt, 
Pl. f. the Red Sea etc., p. 158; Cleve, Atlant. Plankt. Organisms p. 328; 
Pl. f. the Indian Ocean and the Malay Archip. p.21; Rhizosolenia? flac- 
cida Castr. Challenger p. 74, Pl. 29, f. 4. 
3(r) — 6(rr) — 10(rr). 
Area: Temperate Atlantic Ocean from Norway southwards to 16° N., Me- 
diterranean, Red Sea, Arafura Sea, Malay Archipelago. 
Rhizosolenia (Ehbg.) Btw. 
23. JR. alata Btw., Micr. Journ. 1858, p. 96, Pl. 5, f..7; Cleve, Diat. 
f. the Sea of Java, 1873, p. 11; Leuduger-Fortmorel, 1. c. p. 36; de Wil- 
deman, |. c. p. 123; Grunow, Novara Exp. p. 28; Peragallo, Monogr. Rhiz. 
p. 115, Pl. 5, f.11: Schréder, Neapel p. 26; Ostenfeld & Schmidt, Red 
Sea p. 159; Cleve, Phytoplankton p, 24; Atlant. Plankt. Organisms p. 337; 
Red Sea p. 1034; -Pl. f. the Atlant. and Indian Ocean p. 934; Pl. f. the 
Ind. Ocean and the Malay Archip. p. 22. 
