796 PERIDIXEAE OF NEW SOUTH WALES, 



DINOFLAGELLATAE or PER1DINEAE. 



Genus Hemidinium Stein . 

 Hemidinium nasutum Stein. (Text-fig. 1, c). 



Long. 24-28, lat. 14-17 y, . Lismore (302, 332, 345, 347); 

 Byron Bay. 



Doubtless widespread in swamps and pools, but only noted 

 from the localities named. Exactly the size given by Schilling. 



Genus Gymnodinium. 



Gymnodinium aeruginosum Stein. 



Specimens noted in March, 1909, from the Gardener's Road 

 swamp, Botany, are supposed to represent this species. In size 

 and appearance they tallied fairly well with the figures given by 

 Schilling (Dinoflagellatae, p. 19, f. 18) but the contents were a 



Text-fig. 1. 

 fa) Glenodinium oculatum var. circulatum, n. var. (x 660) ; (b) Gym- 

 nodinium paradoxmn Schilling, forma (x 660); (c) Hemidinium 

 nasutum Stein (x 1000). 



Text-fig.2. 

 (a) Gymnodinium australe mini ; (b, c) var. acutum, n. var. (x500). 



