NORTH ATLANTIC PLANKTON. 59 



Diatoms {Coscinodiscus, &c.) and Halosphcera. 

 Limacina retroversa. 

 Nauplei, and Megalopa (large). 

 Copepoda : — Calanus finmarcliicus (abundant). 

 Pseudocalanus elongatus (abundant). 

 Oithona spinifrons (abundant). 



VI. September 28th, 7 p.m., to September 29th, 9 a.m.; 

 from lat. 52° 8' N., long. 54° 30' W., to lat. 53° 25' N., 

 long. 49° 20' W. (Very large gathering, phosphorescent.) 



Ceratium tripos (common), and Chcetoceras. 



Peridinium diver gens (common). 



Tintinnus denticulatus, and Codonella ortlioceras. 



Megalopa of Crab. 

 Copepoda : — Calanus propinquus (common). 



C '. finmarcliicus* (masses of large, red). 



Pseudocalanus elongatus (abundant). 



Oithona spinifrons (common). 

 F, on bath tap, September 29th, 7 to 11 a.m. 



Ceratium tripos, and Coscinodiscus radiatus. 



Peridinium diver gens (2 varieties). 



Tintinnus denticulatus, and Codonella ortlioceras. 



Globigerina bulloides. 



Calanus finmarchicus (few) . 



VII. September 29th, 9 a.m. to 6 p.m. ; from lat. 

 53° 25' N., long. 49° 20' W., to lat. 54° 15' N., long. 

 46° 22' W. ; temp. 49° F. 



Ceratium tripos, and C. furca (abundant) . 

 Peridinium sp. (common). 

 Tintinnus denticulatus (common). 

 Codonella campanella. 

 Globigerina bulloides (abundant). 

 Coscinodiscus radiatus (common). 



* Some of these were cooked by Mrs. William Ramsay, and were eaten 

 by the captain and a number of the passengers (see Nature, vol 56, p. 565). 



