292 bulletin: museum of comparative zoology. 



four foot and Helgoland nets failed to capture it at seven out of these 

 thirteen stations. Probably their larger mesh allowed this minute 

 species to pass through. The coarse nets alone being used for the 

 subsurface work in the water south and west of Cape Cod, the apparent 

 absence of this species there may have been partly due to the appara- 

 tus. But it can hardly have been abundant there, or it would have 

 appeared occasionally in the catches of the four foot net, just as it 

 did in the Gulf of Maine. And this agrees with Williams's observa- 

 tion (1906) that it is only in winter that Pseudocalanus appears in 

 Narragansett Bay. In July and August it is abundant off Nova Scotia 

 (Wright, 1907). ^ 



Eucheata norvegica was taken at practically every deep haul in the 

 Gulf; as well as in three hauls from twenty fathoms (Stations 10090, 

 10091, 10101), one from fifteen fathoms (Station 10104) and one sur- 

 face haul (Station 10097). It was found only once south of Cape Cod 

 (Station 10061, 70-0 fathoms). The largest numbers were yielded 

 by the deeper hauls, e. g., 90-0 fathoms at Station 10100; 80-0 fath- 

 oms at Stations 10088 and 10097; 75-0 fathoms at Station 10090; 

 70-0 fathoms at Station 10061. At Stations 10092 and 10097 it was 

 as abundant in the hauls at thirty fathoms, as in the deep hauls, 

 and this was an interesting phenomenon for it was at these same 

 stations that Calanus was uniformly distributed from the surface 

 downward instead of being localized in the mid layers (p. 290). Eu- 

 chaeta is never abundant in the Gulf of Maine, in the sense that Cala- 

 nus, or any of the other small copepods can be so described, the richest 

 hauls yielding a couple of hundred specimens at most. It occurred in 

 only three of the quantitative hauls, and then only in small numbers 

 (p. 286) ; but since the other nets yielded considerable numbers where 

 the quantitative nets missed it, it is probably sufficiently active to 

 avoid the latter, just as the Sagittae are (p. 329). Euchaeta was 

 living in water colder than 50° ; and at a comparatively high salinity 

 (33%o-34%o) ; and its quantitative occurrence indicates the lower 

 temperature and higher salinity for its optimum. The exceptions 

 afforded by the one surface capture, and by its abundance at thirty 

 fathoms at Stations 10092 and 10097, where the salinity was about 

 32.9-33%o are probably due to local causes. 



Metridia longa was likewise restricted to the Gulf of Maine in marked 

 contrast to its relative M. lucens. Its captures are too few to allow 

 any general statement of its range in our waters; but the fact that it 

 occurred at all is of interest because it is the "most typically Arctic 

 copepod of whose distribution there is any accurate knowledge" 



