122 bulletin: museum of comparative zoology. 



chusetts Bay, off Portland, on Piatt's and Jeffrey's Banks, over the 

 Eastern Basin, on German Bank, and off the coast of Maine. But the 

 table of specimens taken at each station shows that the only ones 

 at which more than five were taken were no. 25,28, 30, 31, 32, and 

 36. Only one specimen was taken in Massachusetts Bay, one off Boon 

 Island (Station 41), one off Monhegan (Station 21), and two each at 

 Stations 19, 22, and 40. Evidently, then, its centre of abundance 

 was off shore. It was not common anywhere near shore. The known 

 salinities and temperatures of the captures are : — 



Station 25 30 fathoms closing net temperature salinity 32. 9%^ 



about 48° 



Station 27 30 fathoms closing net temperature 46° salinity 33.3%o 



Station 30 surface temperature 52° salinity 32. 7%o 



Station 32 surface temperature 57° salinity 32. 5%^ 



The other captures were in open nets. The largest hauls were at 

 Stations 31 and 32, where swarms were taken. 



Comparison between the occurrence of S. serratodentata and S. 

 elegans shows an interesting difference in quantitative distribution. 

 The latter was taken at even more stations than the former, very gener- 

 ally over the whole area, including bays and harbors. It occurred in 

 great numbers at Stations 2 and 7, where no serratodentata were taken, 

 and also at Station 44, where we captured only one serratodentata. 

 Swarms of S. elegans were also encountered at Stations 12 and 14, 

 where serratodentata w^as absent. At Stations 19, 20, 25, 27, 33, 38, 40, 

 44, it was numerous, from 10 to 30 or more specimens being taken at 

 each, where serratodentata was represented by only a few specimens; 

 and at Station 30 we encountered a swarm. On the other hand, at 

 Stations 28, 31, 32, where we met swarms of serratodentata, they far 

 outnumbered the elegans, as shown in the accompanying table. 



Number of specimens 

 Station S. elegans S. serratodentata 



2 25 



6 2 



7 swarm 



11 4 



12 swarm 

 14 20 



19 15 2 



20 30 



