— 218 — 



Goniodoma Stein. 



19. G. acuminatum Stein, PL VII, f. 1 — 16. 



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

 Area: Atlantic, Mediterranean, Red Sea, Indian Ocean, Pacific. 



20. ii. arma tu m (Schütt) ; G. acuminatum var. armata Schütt, Die 

 Peridinieen Pl. IX, fig. 32; G. fimbriatum Murray & Whitting, Transactions 

 of the Linnean Society of London, 2 nd Ser., Botany, Vol. V, Part 9, 

 1899, p. 325, Pl. XXVII, fig. 1 a, b. 



3 (it) - 4 (it) - 10 (it). 



Area: Atlantic, Red Sea, Indian Ocean, Pacific. 



Diplopsalis Bergh. 



21. D. lentioula Bergh, 1. c. Pl. XVI, fig. 60 — 62. 



l(-f) - 2 (it) - 3 (rr) - 10(+). 



Area: Atlantic, Mediterranean. Red Sea, Indian Ocean, Pacific. 



22. D. saecularis Murray & Whitting 1. c. p. 325, PI. XXVIII, fig. 5 a, b. 



10 (IT). 



Area: Atlantic from a little south of the Azores to the Isthmus of Panama, 

 Red Sea, Indian Ocean. 



Ostreopsis Schm. now gen. 



Body flattened, oyster-shaped. Apex excentric, marked by a 

 narrow, slit-shaped area. Longitudinal girdle small, not proceeding 

 to apex, only to be seen on the inferior valve. 3 apical plates 

 (one of which being reduced) and 1 antapical plate are present. 

 Structure of plates porous. 



Fig. 5. Ostreopsis siamensis Schmidt. Fig. 6. Ostreopsis siamensis Schmidt. 

 Arrangement of plates in the Another specimen. Arrangement of 



superior valve. plates in the inferior valve. 



