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BULLETIN OF THE BUREAU OF FISHERIES 
Brady, as he himself admitted in his later writings, confused the two genera, Artotragus and Astero- 
cheres, and should have assigned his species to the latter instead of the former. Most of the species 
of this genus are parasitic upon, or commensal with, some invertebrate animal, but Brady gave no 
information upon this point. Scott, in his “Catalogue of the Crustacea of the River Forth,” 
reported obtaining this species in the water passages of sponges ( Chalina oculata ) growing on the 
walls of a pier. It was later recorded by Norman and Brady from a tidal pool on the coast of 
England, and it was added that this was probably a truly commensal or parasitic species, acci- 
dentally found in a free condition. This readily explains why more specimens were not found in 
the present collections, and it is significant that these two came from close to the coast of Maine 
south of Portland [station 20059], 
Calanus finmarchicus (Gunnerus ) 11 
General distribution . — Farran (1910, p. 83), whose words I can not better, 
has described the distribution of Calanus finmarchicus as “centered in the North 
Atlantic. It has also been recorded from the South Atlantic off Cape Colony, the 
west coast of South and North America, 96 the Mediterranean, the Adriatic, and the 
Polar Ocean.” Following the North Atlantic around from east to west, we find 
it occurring in dense though limited swarms off the mouth of the English Channel 
(Farran, 1910); on the south and west coasts of Ireland, where Farran (1903) found 
it the most abundant and economically important of the copepods ; and on the west 
coast of Scotland (T. Scott, 1898, p. 182). Many authors have described the ex- 
traordinary abundance of this species in Norwegian seas. Gran (1902), Paulsen 
(1906), and Damas (1905), in particular, comment on the shoals of it between Nor- 
way, Iceland, and Greenland. The Ingolf expedition (With, 1915) had it at many 
localities off west and east Greenland. Sars (1900, p. 35) describes it as “by far the 
commonest of all the Copepoda in the north polar basin explored by the Fram 
expedition, forming, indeed, in all the samples the great bulk of the contents.” 
Cleve (1900) remarked its abundance in the Labrador current. Herdman, Thomp- 
son, and Scott (1898) record it from practically every tow netting across the North 
Atlantic from Liverpool to the Straits of Belle Isle — largest in the Labrador current — 
and Farran (1910, p. 83) speaks of it as “in great abundance along the coast of North 
America in the path of the Labrador current, forming, in the summer months, a 
rich belt, which, off Newfoundland, is at least 500 miles wide. ” Corroborating this, 
the international ice patrol has taken great masses of it on the Grand Banks; Willey 
(1919) found it the commonest copepod between Nova Scotia and the Newfoundland 
Banks, in the Gulf of St. Lawrence, and along the outer coast of Nova Scotia. 
It dominates the plankton of the Gulf of Maine at all seasons, as will shortly 
be described, and outside the immediate coastal zone is usually plentiful and often 
the dominant copepod over the continental shelf off southern New England to longi- 
tude about 72° W. ; that is, abreast of Long Island, New York (Bigelow, 1915). South 
of this its occurrence along the seaboard of the United States becomes more seasonal 
and less regular. It is to be expected in abundance over the shelf between the 
latitudes of New York and Chesapeake Bay during the cold half of the year and into 
early summer, Rathbun (1889) having found it characterizing the plankton at many 
88 According to With (1915) the relationship of C. helgolandicus Sars to C. finmarchicus is still in doubt, but Dr. C. B. Wilson 
writes “ Whatever may be the outcome, it seems reasonably certain that all the specimens from the Gulf of Maine are finmarchicus.” 
88 Esterly (1905, p. 126) describes it as the commonest copepod about San Diego, Calif., and as often very predominant. 
