;{()() OvK l'Ai i,si;n. 



Goiiiodoina Slcin. 



<). Goniodoma Ostenfeldii Paulsen, Plankton invest. Iceland 

 1*)Ü3, [). 2(1, lig. 2; Nord. Planklon p. 34, lig. 43; Broch Spitzbergen 

 Planklon p. 32, lig. 3. 



Found in single specimens in Danmarks Havn, the coastal water, 

 and the open sea. 



I) i si ril). Arclii-. lurilic sjjecies, known IVoin Nurlh-icchuKl mid Si)ilz- 

 herL^i'ii. 



Peridinium Ehrenberg. 



Of late years dilTerenl methods of shortly designating the plates 

 composing the skeleton of Peridiiiiiim have been proposed. The first 

 was that of Fauré-Fremiet, whose paper "Étude descriptive des péri- 

 diniens et des infusoires ciliés du plankton de la baie de la Hougue" 

 was published in 1908 in Annales des sc. naturelles, zoologie. Fauré- 

 Fremiet designates the plates by letters with annexed numbers, so 

 e. g. the precingulars are named d^ — d-, d, being to the right, d, 

 to the left, dg to the right and so on. This method seems to me 

 not to be practical. 



Next to Fauré-Fremiet comes Kofoid, the well-known investiga- 

 tor of the Dinotlagellates. His paper "On Peridinium Steini Jørgen- 

 sen, with a note on the nomenclature of the skeleton of the Peridi- 

 nidae" was published in 1909 in Archiv für Protistenkunde 16. Kofoid 

 employs only numerals, the different series of plates being distingu- 

 ished by difTerent numbers of apostrophes or other signs annexed 

 to the numerals. So, the apicals are 1'— 4', intercalaries I'' — 3°, 

 precingulars 1"— 7", postcingulars 1'"— 5"', antapicals i""_2"". Each 

 series begins on the left side of the body and goes round it to the 

 right side. This system is a clear one, but not very practical be- 

 cause of the apostrophes as to whose numbers mistakes are likely 

 to arise ^ 



Broch in his paper on Sj)ilzbergen plankton (1910) gives a new 

 method of designating the plates. He uses both numerals and let- 

 ters. In the same year the method was modified in "Die Peridi- 

 nium-Arten des Nordhafens (Val di Bora) bei Rovigno im Jahre 1909" 

 (Arch. f. Protistenk. 20). Here, the apicals are named 1—4 and the 

 precingulars a — g, 1 being the rhomb-plate and a the precingular 

 neighbouring it to the left, and both series go round the body to 



* From the table wliere Kofoid has arranged previous nomenclatures it appears 

 that he has not realized the difference between „tafeln" and „platten'- as these 

 termini were used b}' Schi" tt and after him also b\- the present author who in 

 Nord. Plankton did use Schitts nomenclature. It might have been mentioned 

 that Schitts „tafeln" represent transverse series of .,plates". Only the inter- 

 calaries were not recognised as a series bv Schi'ti. 



