;{()4 OvK I»\ri.si;N. 



The folloNving papers deal with llie Peridiiiiales ol" llie I'"asl- 

 (ii-eenland sea : 



(<i.i:vi;. I'. T. : Hcpurt on tlu' PUmktoii tollfticd b\ tlic S\M'clisli oxpi'dilioii to Spitz- 



hor^'eii in 18!»8. (K. Svciiska \'ct. Akad. Handl. ;{2. IX!)!)). 

 l\\i i.si:n, ()\i. : Plankton investi;^ati()ns in tiic waters round Iceland in l!)(t;} (Meddel. 



fra Kommis, for Havundersøg. Ser. Plankton, lid. I. Xo. 1 1!(()4|. (Cited as: 



Plankton invest Iceland 1!»()3). 

 l)ii()( n, ll.i. : l*lankton tables. In Damas et Koefoed: Le plankton de la mer dn (iron- 

 iand. (Duc d Orleans : Ci'oisière océanograi)hi(|ue aecomplie :'■ bord de la Helf^ica 



dans la mer du Grönland lüOf)). Bru.xelles !!)()!). 

 Pali.skn, Ovk: Plankton investijrations in tbe wateis round leeland and in tlie Nortli 



Atlantic in 1!)04. (Meddel, fra Kommis, for Havundersøg. Ser. Pankton. lid. I. 



No. 8). 19Ü!). 

 HuocH, Hj.xlmah: Das Plankton (Zoologiscbe Ergebnisse der Schwedischen li.xpedition 



nach Spitzbergen 1908. Teil I, 2). (K. Svenska Vet. Akad. Handl. 45, No. 9. 1910)'. 



(Cited as: Broch, Spitzbergen Plankton . 



Yet, for easy reference, b}' each species the following paper is cited: 

 Pailskn, Ovk: Peridiniales (Nordisches Plankton, herausgeg. v. Brandt u. Apstein 

 XVlll). Kiel 19(18. 



Dinophysis Ehrenberg. 



1. Dinophysis norvegica Claparède & Lacliniann, Mém. inst, 

 nat. Genév. 1859, p. 407, lab. XX, lig. 19. Paulsen Nord. Plankton, 

 p. 14, fig. 11 — 12. Broch Spitzbergen plankton 1910, p. 31, fig. 1, I. 

 D. acuta auct. [)lur., non Clap. Lachni. 



Single specimens, agreeing with var. crassior, Paulsen 1. c. and 

 also \vith Brochs drawing, were found in the outer part of the pack- 

 ice and in the open sea. 



Distrib. Seems to be a neritie and boreal but bardly arctic species. 



2. Dinophysis arctica Mereschkowsky, Archiv f. mikroskop. 

 Anatomie 1879, p. 177, tab. XI, fig. 19. Paulsen Nord. Plankton 

 p. 15, fig. 14 (a bad figure), Broch Spitzbergen plankton p. 31, fig. 1, 

 II. D. graiuilata Cleve & aucl. plur. 



Broch (I. c.) says that this species bears fine and distant poroids 

 on the surface while D. norvegica is coarsely areolated. My annexed 

 fig. 1 shows that Ibis is not always the case, this specimen (and 

 many others) being very coarsely areolated. Besides, I have often 

 found cells of this species provided with small protuberances at the 



' In this paper which appeared as I had finished the examination of the plankton 

 samples, Bütschlis theory on the intercalarj' striae as growth-marks is shown to 

 hold good, the growth of the different species is studied in detail, and the 

 arrangement of their plates is expressed in formulae. It will really be an ad- 

 vantage if the plate-arrangement proves to be so constant as supposed bj' Broch. 

 — A lack in Broch's paper is that he gives no measures of the organisms, he 

 confines himself to criticise those given In' me. His paper will be often men- 

 tioned in the following. 



