DlAl'n.MAi.K.K — STi;i;i'T( tTll K( ;A. 'I'lf ALASSIOSIK.V 853 



STREPTOTHECA THAMESIS Shrubs. 

 (CI. A Treatise on llic l'liyl.>-|ilaiikt(.ii I'l. II lig. 19.) 



189S January: 48'" N. 6 W. 



March: 45= N. H(r W. 



April: 58' N. 2 \V. 

 lsii!» Mai-rli: 48' N. (i W. 



April: 50- N. (> W. 



Temperature; I <».:;. mean of 5 obs.. max. i:; iniii. 8. 



Salinity: H5. .-,•... 



Plankton-type. This species oceur.s in Ihe southern North 

 Sea, in the mouth of the river Thames, at the coasts of Scotland, 

 but in the Atlantic only occasionally. The above mean salinity it 

 therefore to be (considered as anomalous. — Xm. 



THALASSIOSIRA GELATINOSA (IIkxskx). 



(A. Schni. Nord .Sea Dial. I'l. XXXVIII lig. ;•}. 



iSilS April: \V,\ X. IS \\'., common. 



1S»)») June: Oi) X. i;; W.; (55- X. 1 W. (doe]) sea haul from 2(H) 

 to m.). 



Temperature: 7. 



Salinity: 2(j..-,i. 



Plankton-type. Found in the Arctic Sea, the North Sea 

 and the Skagerak. It occurs also in the northern Pacilic (betwoeu 

 Vancover Island and Hritish Columbia, Lk.mmkrman.x). — A//. 



THALASSIOSIRA GRAVIDA Cl.' 



(Bill. Kongl. Sv. Vetensk. Akad. Iriandl. Vol. XXII H ii. 4- I'l. II lig. 14— Hi, ^ (iR.w. 

 I). Norske Xordliavs Kxped. lS7(i — 7S Protoidiyla I'l. IV lig. .')7— 58. 



KS'.is March: 71- N. 5 \\'.. rare; 58- N. (> K; Fiiriies. rare; 40- N. 

 (i8 — ()<.h w. 

 April: ()() N. 24 W'., common; S. of Iceland, not rare; Fiir- 

 oes, rare; W. of the Siictlands. rare; i2 N. \1 \\ . and 

 40=^ N. ()8^ W., rare. 



Ostenfeld's data used. 



2)S 



