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 be 



haps forming a connection between 



the Chaetocereae and the Biddul- Fig. 20. SchmddtieUa pelagica Ostf. 

 phieae. u chain of two cells in front view, b in 



sagittal view, c cell in side view (lp).- 



62. S. pelagica Ostf. n. sp. 



Characters of the genus, frustules in front view 80^ broad, in 

 sagittal view 40^ broad. 



1 have only found one chain of this interesting diatom which I name 

 in honour of the Danish botanist Johs. Schmidt w T ho made those rich 

 collections in Siam w T hich he is publishing in the „Flora of Koh Chang". 



Eucampia Ehbg. 



63. E. b icon cava (Gl.) Ostf. ms. ; Climacodium biconcavum Cleve, 

 Phytoplankton p. 22, PI. 2, f. 16,17; Atl. Plank t. Organisms p. 314; PI. 

 f. the Red Sea, p. 1033; PI. f. the Indian Ocean and the Malay Archip. 

 p. 19; Eucampia hemiauloides Ostf. in Ostenfeld & Schmidt, PI. f. the 

 Red Sea p. 157, f. 9. 



According to a letter from Mr. Cleve his Climacodium biconcavum is 

 identical with my Eucampia hemiauloides, and consequently his species- 

 name has the priority, but as shown in my paper it must be an Eucampia, 

 with the same structure as the other species of this genus. 



2 (r) - 3 (it) - 4 (rr) — 5 (it) - 6 (it) — 7 (r) - 10 (rr). 



Area: Tropical Atlantic Ocean, Mediterranean, Red Sea, Gulf of Aden, 

 Malay Archipelago. 



64. E. cornuta (CI.) Grun. in Van Heurck, Synopsis PI. 95 bis, f. 5; 

 Cleve, Pl. f. the Red Sea p. 1033, PI. f. the Indian Ocean and the Malay 

 Archip. p. 21; (?) Atl. Plankt. Organisms p. 326 ; Mölleria 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). 



