H22 DIATOMACE,^: — COSCIXODISCU.S 



COSCINODISCUS (PLANKTONIELLA) SOL. Wallicii. 



(A. Sclim. Atl. PI. LVIII lig. in). 



J SOS J(uiiuu-y: 0' S. -IW W.; ](>- N. 18^ W.; m^ N. Hir W. to 



Mr N. 11' W.; 7 — Jl" X. oH^— 52° W.; Ho'^ N. 71' W. 

 March: 1' S. 15' — 2()' W.; area between the Azores, the E. 



Channel and !<)' N. 88' W.; :}2° N. 71' W. 

 April: area between the Azores, the V^w^]. Channel and Tr 



N. lO' W.; ar N. 75° W. 

 May: area between Cape Finisterre, 11' N. KV" W , 18° N. 



Ifr W. and 50' N. 11^ W. (most <-oinmon north of 15' N.); 



11' X. 59° W. 

 Jtiiic: i()'— 50' N. 12" W., rare. 

 Octohi'/': 57' X. 1S' W., rare. 

 Xorcmbei': 0° S. H1° W.; area between IS" X. 20'— iF W. 



and 55°— 5B° X. 2!°— 28° W. 

 mw) Jdinuiry: 88^ X. 15° W.; 1-8°— 50" X. and 80'— 20' W.. rare. 

 March: 1(i° X. 11° W. 



April: area between 11—11 X. 15° W. and 12' X. IS W. 

 May: 82' S. 18° K. 

 J ma-: 20' S. 1° E. to 15" S. 5" K. 

 Octohcr: 52' X. 11° W.; 5()° X. 28° W.. rare. 

 Xorcinhcr: 51° N. 18° W., rare. 



Temperature: 15.,-,, mean of 72 obs., max. 27, min. 0. 



Salinity: 85. so, mean of 5(') obs, max. ;)()..;i, inin. 8 1.4s; excep- 

 tionally 20.:!.i and 22. -,i. 



Plankton-type. Noted from the Indian, Pacilic, Mediterranean 

 and Ked Sea. It occurs in the Atlantic along the west coast of 

 Africa, in March and April between the Azores and the E. Channel; 

 advances in May beyond 45° N. From May rare or absent in that 

 region. In September rare specimens had drifted towards Rockall. 

 In November it reappeared between IS' X. and 5(i° X. It has been 

 rarely seen in the western Atlantic, in the Florida current. — N. 



