Hr){i DIATOINIACEyK — TIIALASSIOTHUIX 



Pacific, at Puget's Sounrl. Lem.\ikr:\ia\x mentions it from Bara 

 Island, between Vancouver Island and the British Columbia. In the 

 years 1871 — 75 it was exceedingly abundant in the arctic regions 

 not only along the coasts, but in the 0})en sea. In the years lS9n 

 — 99 it had not that important part in the arctic plankton. — A/y. 



THALASSIOTHRIX FAUENFELDII Gnux.^ 

 (Va\ Heirck Syn. PI. XXXVII (ig. 11—12). 



1898 March: 21^ N. 18MV.. rare; til' N. 11" W., common; 58^ N. 



6^ E. 

 April: 39'" N. 24-" W.; S. of Iceland; 59"— (JO" N. 4"— 29" W. 

 May: 60" N. 9 W. to 57- N. 28" W., common N. and \Y. of 



Bockall. 

 June: 63" N. 19" W. to 60" N. 7" W., rare. 

 Jahr- S. and W. of Iceland; ()0 N. 17" W. 

 Scptcinhcr: 60" N. 11" W. 



Octohcr: 61" N. 5" W. to 57^ N. 27" W., more or less rare. 

 NovciDlu'r: S. Iceland to the Shetlands, more or less rare. 

 Decc'inber: (51" N. 6" \V., rare; 62" N. 1(>" W. not rare. 



1899 April: 48" N. 9" W., rare. 

 Mai/: 58" N. 4" — 7" E.; common. 



Temperature: lO.i, mean of 11 obs., max. 15, min. 6. 

 Salinity: 34.1-4, mean of 8 obs., max. 35..-,.-,, min. 26. 51. 

 Plankton-type. Noted from Japan. — A"s. 



liciiKiri,-. Most of the above data are from Ostc/ifcld. I have 

 foimd this form only very rarely in tlie ocean, but very abundantly 

 during the winter and spring in the plankton of the Skagerak. If 

 may be possible that at least some of Ostenfeld's data relate to the 

 varietv Jaranica. 



Ostenfeld's data used. 



