Biddulphieae. 
Schmidtiella Ostf. n. gen. 
Frustules in chains. Valves broadly elliptic with undulate 
surface, most elevated at the 
sagittal plane, cohering one to 
another by two minute processes 
at the sagittal plane. Frustules 
in a front-view rectangular. No 
structure seen. Endochrome coc- 
cochromatic. 
Allied to Graya Brun & Grove 
[see Van Heurck, A Treatise on the 
Diatomaceae p. 458, f. 187] and per- a b ¢ 
haps forming a connection between 
the Chaetocereae and the Biddul- Fig. 20. Schmidtiella pelagica Ost. 
phieae. a chain of two cells in front view, 6 in 
sagittal view, ¢ cell in side view (29°). 
62. §S. pelagica Ostf. n. sp. 
Characters of the genus, frustules in front view 80, broad, in 
sagittal view 40 broad. 
I have only found one chain of this interesting diatom which I name 
in honour of the Danish botanist Johs. Schmidt who made those rich 
collections in Siam which he is publishing in the ,Flora of Koh Chang“. 
Eucampia Ehbg. 
63. E. biconeava (Cl.) Ostf. ms.; Climacodium biconcavum Cleve, 
Phytoplankton p. 22, Pl. 2, f. 16,17; Atl. Plankt. Organisms p. 314; PI. 
f. the Red Sea, p. 1033; Pl. f. the Indian Ocean and the Malay Archip. 
p. 19; Eucampia hemiauloides Ostf. in Ostenfeld & Schmidt, Pl. f. the 
Red Sea p. 157, f. 9. 
According to a letter from Mr. Cleve his Climacodium biconcavum is 
identical with my Hucampia hemiauloides, and consequently his species- 
name has the priority, but as shown in my paper it must be an Hucampia, 
with the same structure as the other species of this genus. 
2(r) — Br) — 4(rr) — 5(rr) — 6 (rr) — 7(r) — 10 (rr). 
Area: Tropical Atlantic Ocean, Mediterranean, Red Sea, Gulf of Aden, 
Malay Archipelago. 
64. E. cornuta (Cl.) Grun. in Van Heurck, Synopsis Pl. 95 bis, f. 5; 
Cleve, Pl. f. the Red Sea p. 1033, Pl. f. the Indian Ocean and the Malay 
Archip. p. 21; (?) Atl. Plankt. Organisms p. 326; Mélleria cornuta Cleve, 
Diat f. the Sea of Java 1873, p.7, Pl. 1, f. 6; Leuduger-Fortmorel, 1. c. 
p. 47. 
6 (rr) — 10(r). 
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