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BULLETIN OF THE BUREAU OF FISHERIES 
instance, is the case in the fjords and along the coast of Norway (Sars, 1903; Farran, 
1910), between Iceland and the Faroes (Wolfenden, 1904), in the Faroe channel, in 
the Gulf of St. Lawrence, and along the outer coast of Nova Scotia (Willey, 1919). 
In the northeastern Atlantic reports of it at the surface have usually been based 
on immature specimens; but this rule does not apply to the Gulf of Maine, Willey 
(1922) having found it in the breeding state close to the surface near St. Andrews. 
Euchssta necessarily inhabits a somewhat shoaler zone in the gulf (with its lower 
limit set at about 300 meters by the topography of the bottom) than in the 
Norwegian sea and between Iceland and the Faroes, where it occurs chiefly below 
200 to 300 meters, and down to 1,000 meters. 
Breeding. — Our failure to find E. norvegica at any time in the eastern or northern 
channels (we have one record of it on Browns Bank, June 24, 1915, station 10296) and 
the fact that its seasonal fluctuations in abundance along the continental shelf are 
not reflected within the gulf are evidence that the maintenance of the Gulf of Maine 
stock depends more on local reproduction than on immigration. Were the opposite 
true, we would expect to find it in the two channels, these being the entrances for 
visitors from the mid-depths offshore, or from the east and north, and most plentiful 
within the gulf at the season when it is most plentiful outside. Adult females with 
egg clusters attached are familiar objects in the deeper Gulf of Maine tows, while 
Willey (1921) has found adult males with spermatophores as well as egg-bearing 
females and immatures of both sexes at St. Andrews. 
Willey’s specimens were taken in February, and since females with egg sacs 
were noted in the Albatross tows on March 3, 1920 (station 20055), and outside the 
continental edge off Shelburne, Nova Scotia, on the 19th (Station 20077), while 
most of the summer catches of the species have contained them, E. norvegica evi- 
dently spawns throughout the year in the Gulf of Maine. The vertical distribution 
of the species proves that reproduction takes place almost entirely below 100 meters, 
though occasional individuals in breeding condition may occur at the surface. 
Relationship to temperature and salinity. — The tendency of this species to keep to 
deep water makes it easy to establish the physical conditions under which it lives in the 
gulf. 
The great majority of the captures have been in comparatively high salinities 
(33 to 34 per mille) and from temperatures lower than 10°, the quantitative occurrence 
of the species pointing to the higher salinity and to a temperature lower than 8° as 
its optimum. Such of the Gulf of Maine stock as lives below 150 meters inhabits a 
zone in which the yearly range of temperature is narrow — for the most part between 
6 and 4°. However, its presence at the surface proves that it can survive a brief 
visit in water as warm as 19 to 20° (stations 10254 and 10256, western basin, August 
22 and 23, 1914). On the other hand, the wide Arctic distribution of E. norvegica 
makes it unlikely that the temperature is ever unfavorably low for it in the Gulf of 
Maine, which is corroborated by its presence near the surface at St. Andrews during 
the coldest season (Willey, 1921). The failure of this species to work farther inward 
toward the Baltic 31 than the Skager-Rak makes it probable that salinities lower than 
51 One record from the Kattegat is mentioned by Farran (1910). 
