— 19 - 



1 (r) - 6 (rr) - 10(+). 

 Area: Malay Archipelago. 



50. C. laeve Leud.-Fortm., 1. c. 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 1 

 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 

 abruptly turning off at a right angle. 

 Ghromatophore a single plate in 

 front. Breadth of the cells 9 — 16^. 



1 (+) - G (rr) - 10 (+). 

 Area: Sea of Java. 



51. C. Lorenzianum Grim., 

 Verhandl. d. k. k. zool.-botan. Ge- 

 sellsch., Wien 1863, p. 157, Pi. 14, 

 f. 13; Cleve, Diat. f. the Sea of 

 Java, 1873, p. 9 ; Leuduger-Fort- 

 morel, 1. c. p. 37; de Wildeman, 

 L c. p. 134; Van Heurck, Synopsis 

 PL 82, f. 2; Cleve, Phytoplankton, 

 p. 21, PLI, f. 13 — 15; Schröder, 

 L c. p. 29 ; Cleve, Pl. f. the Red 



Fig. 16. Chaetoceras laeve Leud.-Fortm. 



4 5 0. 



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. 306; 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(c). 



Area: Atlantic from North Sea southwards, Mediterranean, Red Sea, Gulf 

 of Aden, Indian Ocean, Malay Archipelago, Hongkong. 



52. C. paradoxuin 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 L c. p. 37. 



2 (rr) - 10 (it). 



Area: Malay Archipelago. 



2* 



