r>79 



lins named Hexasterias problematica , most naturally has its place 



in the neighbourhood of the genus Pterosperma. 



Around the Færoes it occurred in a few specimens in July, No- 

 vember, December. February and March. It seems to be ;i boreal-tem- 

 perate, oceanic species. 



III. Peridiniaceae. 



I. EXUVIAELLA Cienkowsky, 1881. 



60. E. compressa (Bail.) Ostf. , Iagttagelser, etc, 1899, p. 59; 

 Pyxidicula compressa Bailey; Dinopyxis compressa Stein, Organismus 

 der Infusionslhiere, III. Abt., II. Hålfte, 1883, PI. I, figs. 34— 38; 

 Exuviaella marina Schutt in Engler & Prantl, Natiirl. Pflanzen- 

 fainilien, I, 1, b, fig. 11; non Cienkowsky. 



A temperate, oceanic species which has only been found in two 

 samples of July 1900; but this mav be accounted for by the faet that 

 its minute size allows it to pass through the meshes of the gauze. 



II. DINOPHYSIS Ehbg., 1839. 



61. D. acuta Ehbg., Abhandl. Berlin. Akad., 1839, p. 151 ; Stein, 

 1. e. PI. 19, lig. 13. 



With regard to the genus Dinophijsis I have followed E. Jør- 

 gensen' s view as expressed in his excellent paper on the species 

 of the »ac7/ta«-group (Bergens Museums Aarbog 1899, VI, pp. 27 — 31). 



The D. acuta s. str. is a borcai- temperate, oceanic species which 

 was found in samples from the Færoes in the months of February, 

 March, July — August. October and December; but always rare. [See tables.] 



62. D. acuminata Claparede & Lachmann, Mém. de l'Instit. 

 Génevois, V— VI, 1858—59, p. 403, PI. 20, fig. 17; Jorgensen, 1. c. 

 p. 30, PI. 1, figs. 7—9; D. Vanhoffenii Ostf., Iagttagelser, etc, 1899, p. 58. 



This boreal, oceanic species being small eseaped through the net 

 and is of course very rare; only found in two samples and in a few 

 specimens (July 1900). 



Note. D. norvegica which I consider as a neritic species occurring along the 

 west-coast of Europe, has not been found around the Færoes. 



63. D. rotundata Clap. & Lachm., 1. c. p. 409, PI. 20, lig. 10; 

 D. Michaelis Auett., an Ehbg.? 



This species also, on account of its small size, eseapes through the 

 meshes, and is only occasionally caught in the net. 



Specimens occurred in July— August, but sparingly. Temperate, 

 oceanic species. 



Botniiy ol' Mie Færdes. •jy 



