804 
Bulletin of the bureau of fisheries 
SALINITY IN MIDWINTER 
The general oceanographic survey of the inner part of the gulf carried out by the 
Halcyon during the last days of December and first half of January, 1920-21, affords 
our only picture of the salinity of the offshore waters for that season. 
These midwinter observations prove interesting from several view points. In 
the first place, when added to the winter records for Massachusetts Bay and for the 
Bay of Fundy for other years they show that little alteration takes place in salinity 
from autumn to midwinter, evidence that this season sees no extensive indraft of 
the saline slope water over the bottom. The regional distribution of salinity in the 
upper 100 meters gives evidence to this same effect, for this was highest near shore 
Fig. 163. — Salinity at the surface, December 29 1920, to January 9, 1921. Contours for every 0.2 per mille 
in the western side of the gulf as in May instead of in the eastern, as is the rule 
at other times of year. This distribution appears most clearly on the surface pro- 
jection (fig. 163), with 32.7 per mille off Cape Ann but only 32.5 per mille in the 
Nova Scotian side of the basin; likewise at 40 meters and at 100 meters, where these 
same localities were the most saline. These, in fact, were the only stations where 
the 100-meter salinity was then higher than 33 per mille, so that this isohaline 
paralleled the northern and western slopes of the gulf at this level. 
The bottom water of the two sides of the basin at 200 meters and deeper then 
proved almost precisely alike in the two sides of the basin (about 33.9 per mille off 
