802 



PERIDINEAE OF NEW SOUTH WALES, 



Text. fig. 7. 



Text-fig.6. 

 Peridinium caudatum var. planktonicum, n. var. from Sydney 

 (text-fig.6) and Brisbane (text.fig.7). (x 1000). 



Syn. P. tabulatum var. africanum (Lemm.) niihi, (P. 

 africanum Lemin.) op. cit., p. 544, PI. lv., f. 17. This form 

 is not identical with P. africanum Lemm. (Cf . G. S. West. Frw. 

 Algae 3rd Tanganyika Exp., p. 188, PL 9, f. 1) though it bears 

 considerable resemblance to it especially when found with inter- 

 calated plates. It is a distinctly ovate form, slightly faceted, 

 with conical epivalve the sides of which, unlike those of the pre- 

 ceding variation, are symmetrical, and the pit apical. The latter 

 is sometimes quite plain, sometimes with a thickened rim and 

 occasionally its edges appear in dorsal and ventral view as 

 minute spines. The hypovalve is as broad as the epivalve, with 

 a slight excavation behind, which indicates the posterior margin 

 of the greatly dilated longitudinal furrow. The antapical plates 

 are large, not quite equal and set somewhat obliquely — quite dif- 

 ferent from those of P. africanum. 



Var. morsum mihi. (Text-fig. 8). 



Epivalva apice in rostrum brevem truncatum producta. Hy- 

 povalva depresso pone latissime excavata. 



Long. 23-28£, lat. 20-2(3 p. Sydney Water Supply (66); 

 Brisbane . 



Syn. P. tabulatum var. pusillum f. morsa Playf., I.e., p. 544, 

 PI. lv., f. 19-21. P. pusillum Penard, Perid. du Leman, PI. iv., 



