132 



K. OKAMURA. 



28. Gonyaulax polyedra Stein. (Pl. V., fig. 35). 



Schütt, 1896, p. 21 ; fig. 29. — Jörgensen, 1900 b, p. 34. 

 Height and breadth (wing exclusive) of the specimen figured are ca. 

 0.0675 mm. 



Loc. in Japan : Prov. Tosa. 



Other known loc. : Baltic Sea ; Atlantic Ocean ; Pacific Ocean. 



29. G. polygramma Stein. (PI. III., fig. 13). 

 Nishikawa, 1901-1903, p. 32. 



In Nov., 1902, the Gonyaulax made sudden appearence in great 

 abundance in the Gulf of Isé and on Sept. 26, 1903, swarms of spores, 

 probably of this species, came into observation in Aguwan, near the -Gulf 

 of Isé. They gave the water a reddish colour ; hence the phenomenon 

 is known to fishermen under the name of " aka-shiwo," i.e., " red-tide," 

 as Mr. Nishikawa has already described in his paper quoted above. 



30. Ornithocercus magnifions Stein. (Pl. IV., fig. 27). 



Schütt, 1896, p. 29; fig. 41. — Id., 1900, p. 18; figs. 8-10. — Murr, 

 and Whitt., 1899, p. 332 ; PI. 32, fig. 2. (Histioneis magnified). 



Specimen figured measures: Height of body ca. 0.05 mm; breadth 

 of body ca 0.06 mm. ; length of one of the longer nerves in the sail 

 0.06 mm. ; height of marginal list ca. o 03 mm. 



Loc. in Japan : Prov. Tosa. 



Other known loc. : Atlantic and Indian Oceans. 



31. Peridinium spinulosum Murr, and Whitt. (PI. III., fig. 14). 



Murr, and Whitt., 1899, p. 328 ; Pl. XXIX., fig. 8. 

 Height of body in specimen figured measures 0.04 mm. ; breadth 

 0.035 mm. 



Loc. in Japan : Prov. Tosa. 



Other known loc. : Atlantic Ocean. 



32. P. conicum (Gran) Ostf. and Schm. (Pl. V., fig. 36). 



Ostf. and Schm., 1901. p. 174. — Gran, 1902, p. 189; fig. 14. — 

 Jörgensen, 1900 b, p. 37 (P. Icnticnlare var michaelis). 



