ARCTIC COPEPODA IN PASSAMAQUODDY BAY. 189 



whole sample presenting the appearance of millet seed. This was 

 the spring Balanus maximum for 1917 at the same station where the 

 Calanus maximum was celebrated earlier in the year. Finally on 

 May 17, the surface tow at the same station yielded 7 cc. of plankton 

 which, apart from some lighter material and few Balanus nauplii, 

 consisted of cypris-larvae of Balanus. It should be added that this 

 remarkable material was well known to Dr. Huntsman who kindly 

 permitted me to examine it. A similar efflorescence has been noted 

 by Professor Herdman in the Irish Sea. In 1907 the nauplii first 

 appeared in the Bay at Port Erin on February 22, attaining their 

 maximum on April 15, and disappearing on April 26. The cypris- 

 larvae were first taken on April 6, rose to the maximum on the same 

 day with the nauplii, and were last caught on May 24. 



The males of C. finmarchicus formerly passed for extremely rare 

 because they only appear in the upper layers at the epoch of repro- 

 duction in the spring (Danias 1905). In the spawning centres of 

 C. finmarchicus, the eggs are stated by Damas to be sometimes so 

 abundant that they constitute one of the principal elements in the 

 plankton in certain regions, tens of millions in a sample, even to the 

 exclusion of other forms. They float at variable depths down to 200 

 metres, but accumulate in the upper layers. Such spawning en masse 

 has not been observed in Canadian waters nor in the Gulf of Maine 

 which would seem to be the southern headquarters of C. finmarchicus 

 in the northwestern Atlantic. O. Paulsen (1906) found C. finmarchi- 

 cus propagating in Icelandic waters to the south of Iceland from 

 March to June. C. W. S. Aurivillius (1898) states that males of 

 C. finmcirchicus were observed fairly generally in the deep water of 

 the Gullmarfjord in the Skagerak in August and September 1897. 

 It is to be presumed that they were derived from the spring spawning 

 of that year in other waters. 



From the examination of rich material collected by Norwegian 

 and Danish vessels, Damas found that the distribution of the great 

 mass of eggs of C. finmarchicus coincides with that of the maxima of 

 frequency of the adults. The abundance is at its height in May and 

 June in the waters of the Gulf Stream around the Faeroe Islands. 

 The meeting of the waters which descend from the north, passing 

 to the east of Jan Mayen island in the Greenland Sea, with the warm 

 and salt Atlantic water, is the new factor which brings these indi- 

 viduals to the "ponte." The stations which traverse the Faeroe- 

 Shetland Channel present a profusion of eggs, whilst a five minute 

 surface tow with a metre net may collect more than a litre of Cope- 



