220 BULLETIN OF THE BUREAU OF FISHERIES 



Centropages hamatus (Lilljeborg) 



This species is so far known from the North Atlantic area between the latitudes 

 of 40° N. and 70° N. (Scott, 1911), including the North Sea and the Baltic— most 

 commonly within a moderate distance of the coast. Sars (1903) describes it as com- 

 mon along the whole west and south coasts of Norway, and, according to Scott (1911, 

 p. 106), it is "one of the more common of the Calanoida met with in the North Sea." 



On the American side it did not appear in the towings made south of New York 

 during the summer of 1913 (Bigelow, 1915, p. 287) or 1916, but was taken off that 

 port on August 26, 1916 (station 10394; Bigelow, 1922, p. 146), and near the Long 

 Island shore on August 1, 1913 (station 10083), which, so far as I can learn, are the 

 most southerly records for it along the United States coast. Northward it becomes 

 more plentiful. Williams (1906) found it in Narragansett Bay in January and Feb- 

 ruary, and it is " nearly always present in the tow at Woods Hole, in Vineyard Sound, 

 and in the Gulf Stream south of Marthas Vineyard," writes Dr. C. B. Wilson. 21 

 Wheeler (1901) also records it as nearly always present in considerable numbers at 

 Woods Hole. Its range includes the Gulf of Maine, as described below. Willey 

 (1919) found it at many localities on the banks and over the deep intervening channel 

 between Nova Scotia and Newfoundland in May, 1915, but not at the more oceanic 

 stations, and restricted to the immediate vicinity of the Nova Scotian coast in July. 

 It is widespread and plentiful in the shoaler parts of the Gulf of St. Lawrence (T. 

 Scott, 1905; Willey, 1919), and Herdman, Thompson, and Scott (1898) report it 

 from the Labrador current off the Straits of Belle Isle out to longitude about 53° 

 W., and again between longitude 28° 24' W. and the coasts of Great Britain, but not 

 over the intervening stretch of ocean. 



Gulf of Maine. — C. hamatus appears only twice in the published lists of Gulf of 

 Maine copepods from the Grampus cruises — viz, occasional specimens off Boothbay 

 on July 26, 1912 (station 10016), and off Cape Porpoise on August 18 of the same 

 year (Bigelow, 1914, pp. 115, 116). It was not taken in the vertical hauls during 

 June, 1915, and at only two of the four August stations (table, p. 298), proving it 

 decidedly uncommon in the open waters of the Gulf during the summer, though it 

 may be more plentiful in estuarine situations, where we have made few hauls. It 

 appeared in about 60 per cent of the September verticals for 1915 (Willey (1919) 

 lists it for 3 out of 10 stations near St. Andrews during that month), and it 

 occurred at about half the October stations in the gulf east and north of Nantucket 

 that year, off Gloucester on October 31 (station 10399) and off Cape Cod on Novem- 

 ber 8 in 1916 (station 10404; Bigelow, 1922, p. 135). No information is available as 

 to its local status in November; but the fact that it occurred at about 50 per cent of 

 the midwinter stations for 1920 and 1921 (table, p. 304) points to its constant and 

 widespread presence throughout autumn and early winter. It was detected in only 

 2 of the 80 vertical hauls made in various parts of the gulf during the spring season 

 of 1920 (table, p. 299), and there were less than 100 per square meter in every case. 



During the month of October in 1915, C. hamatus averaged about 9,000 per square 

 meter at the several stations where it occurred to the eastward and northward of 



" In a letter. 



