SEA-FISHERIES LABORATORY. 365 



Cupulita sarsi has occurred several times during 

 recent years in the English Channel, and around the 

 coasts of Ireland, but is still distinctly rare in British 

 coastal waters, and may probably always be taken as an 

 indication of an influx of Atlantic water. 



Doliolum tritonis was first found* by Sir John 

 Murray in 1883 during the cruise of the "Triton" in 

 the Faroe Channel. On that occasion the specimens 

 (which were so abundant that they masked the other con- 

 tents of the tow-net, and between five and six thousand 

 were brought back as a sample) were found to be drifting 

 from the open Atlantic in the S.W. to the " Wyville- 

 Thomson ridge " in the N.E. They were apparently 

 plentiful during the greater part of the cruise, and so 

 must have been present in that region of the North 

 Atlantic in extraordinary profusion. Since the " Triton " 

 expedition, this species has been found t by the Irish 

 Fishery cruiser " Helga " and by the German Plankton 

 Expedition on several occasions in the North Atlantic 

 outside Ireland and in the Faroe Channel; but it has 

 never, so far as we are aware, been recorded inside the 

 Hebrides in such waters as we obtained it from this 

 summer. 



It is interesting to note that last year (1911), when 

 none of the above-mentioned Atlantic forms were 

 obtained, we found quantities of the oceanic pelagic 

 Pteropod Limacina retroversa at many localities from 

 the north of Mull to the Shetlands, while this year not 

 a single Pteropod was seen. 



Both 1911 and 1912 have been exceptional summers, 

 and form a marked contrast in weather. August 1911 

 was unusually hot and dry, and the heat of the month 



* See Herdman, Trans. Roy. Soc, Edinburgh. 



t See Farran, Fisheries Ireland Sci. Investgs., 1906, I. 



