19 237 
.1 (rv) — 6 (rr) — 10(+). 
Area: Malay Archipelago. 
50. @. laeve Leud.-Fortm., lc. p.38, Pl. 6, f. 2. 
Leuduger-Fortmorel has 
(in his treatise on the diatoms of \ 
the Malay Archipelago) described \ 
and figured two species of Chae- 
toceras, viz. C. rude and‘ C. laeve. 
The first of those is only a form 
of C. diversum Cleve, but the latter 
is a distinct species of which | 
here give a figure; it is related 
to C. diversum, but the thickened 
intercalary awns are smooth and | 
of a characteristic curvature, first } 
being nearly parallel and then H 
abruptly turning off at a right angle. 
Chromatophore a single plate in 
front. Breadth of the cells 9-16. 
1 (+) — 6(rr) ~ 10(+). 
Area: Sea of Java. 
51. €. Lorenzianum Grun., 
Verhandl. d. k. k. zool.-botan. Ge- 
sellsch., Wien 1863, p. 157, Pl. 14, 
f. 13; Cleve, Diat. f. the Sea of 
Java, 1873, p.9; Leuduger-Fort- 
morel, 1. c. p.37; de Wildeman, 
lic. p. 184; Van Heurck, Synopsis 
Pl. 82, f.2; Cleve, Phytoplankton, . 
p.21, Pl. I, f.13—15; Schréder, Fig. 16. enenertas Wece Leud.-Fortm. 
lc. p.29; Cleve, Pl. f. the Red Cr). 
Sea p. 1033; Ostenfeld & Schmidt, Pl. f. the Red Sea, etc. p. 154; Cleve, 
Pl. f. the Ind. Ocean and the Malay Archip. p.19; Atl. Plankt. Organisms 
p. 806; C. cellulosum Lauder, Trans. Micr. Soc. 1864, p. 78, Pl. 8, f. 12; 
C. distans, forma setis evidentius punctatis Van Heurck, Syn. P. 82, f. 4. 
Rather common: 1(+) — 2(rr) — 3(rr) — 6 (rr) — 10(e). 
Area: Atlantic from North Sea southwards, Mediterranean, Red Sea, Gulf 
of Aden, Indian Ocean, Malay Archipelago, Hongkong. 
52. ©. paradoxum Cleve, Diat. f. the Sea of Java 1873, p.10, Pl. 3, 
f.16; Pl. f. the Ind. Ocean and the Malay Archip. p.19 and p.55; Leu- 
duger-Fortmorel ].¢. p. 37. 
2(rr) — 10 (rr). 
Area: Malay Archipelago. 
