BIGELOW: COAST WATER EXPLORATION OF 1913. 293 



(Farran, 1910, p. 70). It was not found in the Gulf in 1912, nor has 

 it been recorded before from American waters. 



The only other species limited to the waters north of Cape Cod was 

 Calanus hypoborevs, which was taken at four stations in the Gulf, 

 both on the surface (Station 10103) and in deep hauls. The only 

 haul which yielded any considerable number was at 90-0 fathoms 

 (Station 10100) ; where the ciuantitative net contained 270 C. hypo- 

 horeus to 5400 C. finmarchicus; at Station 10092 the relative numbers 

 were 80 to 88008. 



All the other copepods found regularly in the Gulf of Maine likewise 

 occurred over the continental shelf south and west of Cape Cod. 

 Centropages typicus was taken irregularly in the Gulf (eight stations) 

 (Fig. 70), but never in large numbers. It did not appear at all in the 

 hauls on George's Bank or on Nantucket Shoals; but it was repre- 

 sented at the shallow Stations south of Long Island (10062, 10063); 

 and at most of the stations on the shelf further south and west. It 

 was not taken at Stations 10064 or 10071 ; but was well represented 

 in the deep haul at Station 10076: and it swarmed south of Nantucket 

 (Station 10062), off Long Island (Station 10066); and on the surface 

 off Fire Island July 13. South of New York it was much less numer- 

 ous, as was the case with copepods as a whole. x\nd it never rivalled 

 the Calanus swarm in abundance (p. 286), for which reason and because 

 of its small size, it must be of comparatively little economic impor- 

 tance in our waters in summer. Centropages was most abundant 

 near the surface, for example, the surface haul at Station 10088 yielded 

 ten times as many specimens as the haul from eighty fathoms, though 

 made with a net of only \ the mouth area. And the discrepancy was 

 even greater at Station 10083, where the surface haul yielded several 

 hundred Centropages, the haul from twenty fathoms only one speci- 

 men. The swarms at Stations 10062 and 10066 were on the surface, 

 and between fifteen fathoms and the surface. The species was living 

 at a rather high temperature (about 54° to 76°) , and rather low salin- 

 ity (31.5%o, surface, Station 10066 to 33.2%o, surface. Station 10074), 

 with an optimum, as suggested by its greatest abundance, of about 



65°-69°and31.5-33%o. 



Temora longicornis was abundant only on Nantucket Shoals (Station 

 10060), i. e., just where Centropages typicus was wanting, and was 

 occasional in the surface tows on George's Bank, south of Long Island 

 (Station 10066) and in the Gulf of Maine. But it was not taken at all 

 outside the continental shelf or over the shelf south of New York. 

 It was most numerous on the surface; for example, the surface haul 



