— 14 — 



species, but I have never seen the true R. Temperei. I have figured a 

 frustule and a part of it, showing the form of the spine. 



3 (rr) - 10 (r). 



Area: Of the main species: Mediterranean, Malay Archipelago; of the var. 

 acuminata : Tropical Atlantic Ocean, Mediterranean, Pacific Ocean at Sandwichs 

 Islands. 



Chaetocereae. 

 Bacteriastrum Shadb. 



37. B. hyalin il in Lauder, Trans. Micr. Soc. 

 1864, p. 8, PI. 3, f. 7 a, b; Cleve, Atl. Plankt. 

 Organisms p. 286; PL f. the Ind. Ocean and 

 the Malay Archip. p. 1 8 and p. 54 ; B. spirillum 

 ex parte and B. varians var. princeps Castr., 

 Challenger pp. 83, 84, PI. 14, f.2, PI. 29, f. 1, 3. 



This interesting species which Lauder has 

 described and figured in 1863, has been forgotten 

 for long time; Cleve has now pointed out that 

 it is a distinct species and I am of the same opi- 

 nion. I think it must be the same species which 

 Castracane in his report on Challenger-Dia- 

 toms has figured and named B. varians var. 

 princeps and also his figure PL 29, f. 1 of B. 

 spirillum belongs hereto. The fig. 9 illustrate 

 this species. 



1 (rr) - 3 (r) - 6 (+) - 10 (+). 

 Area: Malay Archipelago, South China Sea. 



38. B. varians Lauder, Trans. Micr. Soc. 1864, p. 8, PL 3, f. 1— 6; 

 Cleve, Diat. f. the Sea of Java 1873, p. 8 ; Grunow, Novara Exp., 1870, 

 p. 28; Leuduger-Fortmorel, I.e. p. 36; Cleve, PL f. the Ind. Ocean and the 

 Malay Archip. p. 18; Schröder, Neapel p. 26 ; Van Heurck, Synopsis, PI. 80, 

 f. 3 — 5; B. varians et var., B.brevispinum et var., B. spirillum ex parte, 

 B. Wallichii, var. hispida Castr., Challenger p. 82 — 84, PL 15, f. 6, 8, 

 PL 19, f. 2, PL 23, f. 1, 3; Actiniscus varians Van Heurck, Synops. PL 82 

 bis, f. 10; B. symmetricum Leuduger-Fortmorel, I.e. p. 36, PL 7, f. 1. 



I regard all the species described by Castracane and Leuduger- 

 Fortmorel as belonging to the very variable B. varians. 



1 (+) - 2 (r) - 3 (rr) - 4 (rr) - 5 (rr) - 6 (+) - 7 (rr) - 10 (c). 



Area: Mediterranean, Red Sea, Gulf of Aden, Indian Sea, Malay Archipelago, 

 South China Sea. A nearly allied form (var. horealis Ostenfeld, Nyt Magazin, 

 Kristiania, 1901, p. 293, f. 5) is common along the Coasts of Western Europe. 



Fig. 9. Bacteriastrum 

 hyalinum Laud. Part of a 

 chain with terminal cell; 

 beneath a terminal cell in 



side view, showing the 

 terminal awns (^p). 



