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BULLETIN OF THE BUREAU OF FISHERIES 
represented in the tow by occasional examples only, even though the water be well 
over 100 meters deep. Its apparent rarity in the southeastern deep of the gulf — I 
say apparent because we have made few tows there — is interesting in connection 
with the probable route which it follows in its journeyings (p. 64). Eukrohnia 
occasionally reaches the trough between the Isles of Shoals and Jeffreys Ledge, 
where we have found it at one station (20093, April 9, 1920) ; but apparently it 
never finds its way into the sink at the mouth of Massachusetts Bay, or at least so 
rarely that we have never taken it there, though we have towed repeatedly at 
various seasons of the year 75 . 
The largest catch of Eukrohnia actually counted so far from any one of our tow- 
net hauls has been 63 specimens (station 10093, haul from 85-0 fathoms, August 12, 
1913). Possibly other haids may have yielded more, but, if so, very rarely. We 
have no reason to suppose that it ever occurs anywhere in the gulf in numbers to 
compare with S. elegans or even with S. serratodentata. 
A catch of 20 to 50 individuals in half an hour’s towing (which may be stated as 
a fair average of the more prolific horizontal hauls, whether made with the 1-meter 
open net or with the slightly smaller closing net) means a very sparse population, 
indeed, when translated into terms of actual density of aggregation in the water — 
say one Eukrohnia to every 30 to 70 cubic meters of sea water. To make this more 
graphic let us say not more than one Eukrohnia in a space the size of an ordinary 
room. 
There is no direct evidence that Eukrohnia breeds within the gulf at any time 
of year, sexually mature specimens never having been found there. Hence the local 
stock is maintained chiefly if not entirely by immigration from centers of production 
elsewhere, but a few large Eukrohnia (up to about 45 millimeters in length) with 
well-developed ovaries were taken among the more numerous immature specimens 
in the deep haul over the slope abreast of Cape Sable on March 19, 1920 (station 
20077). 
Eukrohnia is never absent from the gulf at any time of year, but our records, 
if they can be taken at face value, point to the late spring and early summer as a 
period of decided scarcity, for only one specimen was taken at our May stations in 
1920 (station 20125), and none at all during May or June in lf)15. 
The stock of Eukrohnia present in the Gulf of Maine fluctuates unmistakably 
and widely from year to year. The summer of 1913, when it occurred in all but one 
of the horizontal hauls deeper than 100 meters and at a total of 10 stations in July 
and August, was the best summer for it in our experience, while the summers of 1912 76 
and 1915 stand at the other extreme. In March and April, 1920, Eukrohnia was 
detected in 60 per cent of all the horizontal hauls deeper than 100 meters, and at 
21 stations scattered far and wide over the gulf; likewise in the deep water along 
the continental slope. 
7i For records of Eukrohnia, 1912 to 1916, see Bigelow, 1914, p. 123; 1915, p. 294; 1917, p. 298; and 1922 pp. 138 and 155. During 
the spring of 1920 it was recognized at stations 20044, 20053, 20055, 20057 20064 20068 20069 ,20074 .20075. 20077, 20079, 20080, 20081 
20086, 20087, 20088, 20093 20097, 20098, 20107, 20112, 20113, 20114, 20116, and 20125, and during the winter of 1920-1921 at stations 10490, 
10494, 10496, 10497, and 10499. 
7 » Found only once in 1912 (Bigelow, 1914, p. 123), three times within the gulf, in July and August, 1915, once on Browns Bank 
and once over the continental slope abreast of Shelburne, Nova Scotia (Bigelow, 1917, p. 298). 
