194 



WILLEY. 



fully mature in sex, came as a surprise. I am indebted to Dr. Hunts- 

 man for the follo\\'ing hydrographic data relating to "Prince" station 

 6. It \\ill be seen that they throw no fresh light upon the special 

 biological features of the plankton: — 



Notwithstanding the negative e\idence afforded by the hydro- 

 graphic determinations, there is still a possibility that the somewhat 

 extraordinary nature of the plankton samples taken off Robbinston 

 at "Prince" station 6 during the winter of 1916-17 can be attributed 

 ultimately to a remote flooding of Arctic water in the Labrador cur- 

 rent from Baffin Bay, acting in conjunction mth the Cabot current 

 issuing from the Gulf of St. La^\Tence and with the tides of the Bay of 

 Fundy. Its proximate causation may have had a more local agency. 

 It is certain that the indi\-iduals of C. hypcrhoreus and Mdridia longa 

 were not produced nor would they reproduce where they were found 

 in the estuary of the St. Croix river, although the exuNiation from 

 stage V to stage VI may easily have occurred within our waters. If 

 we may judge from their store of oil, they had thri\-en amazingly 

 during their wanderings and would have had a good chance to avail 

 themseh'es of reversed currents to regain their spawning area in the 

 north. Failing this, they would presumably perish as stragglers with- 

 out lea\nng descendants. Not only do they occur in the Baffin Bay 

 region to the west of Greenland, but they attain their largest dimen- 

 sions there (Aurivillius 1896). Both species were taken in the Dol- 

 phin and Union Strait by the Canadian Arctic Expedition. 



In conclusion it cannot be pretended that our knowledge of the 

 great northern currents, which is so essential in connection with 

 fishery problems, is materially advanced by the present contribution. 

 Its chief claim to consideration is the biological interest appertaining 

 to the identification of the rare males of the hyperborean Calanus in 

 comparatively shallow water a little above the forty-fifth parallel of 

 latitude. 



