450 BULLETIN OF THE BUREAU OF FISHERIES. 
are presented in a series of tables, and likewise on charts 211 to 214, giving the 
location of the stations. 
The average monthly temperature of the water off the Government wharf in Great 
Harbor, Woods Hole, for the years 1902-1906 (five years) is given in table 10, page 
47, and the seasonal changes are portrayed graphically in chart 219. It will be seen 
that during January, February, and March the mean temperature was below 35° F. 
The period when the temperature was below 35° actually extended from about 
December 25 to March 15, and this may be considered the winter season. After March 
15 the temperature rose rapidly, passing 60° about June 1; this constitutes a spring 
season. Between June 1 and October 12 the temperature remained above 60°, holding 
between 69° and 71° from July 11 to August 28, a period of 48 days; this is the long 
summer season of warm water. After October 12 the temperature fell rapidly from 60°, 
until December 11, when it reached 37°, and it remained between 37° and 35° until 
December 26, when it passed below 35°; this period may be considered the autumn 
season. A table of averages such as that of table 10 does not give the extremes of 
temperature, the lowest of which was 28)4° in January and February, and the highest 
74° in July and 74.5° in August. It should also be remembered that the extremes are 
much greater in situations more sheltered than Great Harbor, Woods Hole, as, for 
example, in the upper portions of Buzzards Bay, where the water may be heavily frozen 
for several weeks and the summer temperature probably rises close to 80°. 
It is very important to contrast the seasonal range of temperature at Woods Hole 
with that of the bottom water between Gay Head and the ledges of Sow and Pigs, for 
in this region of the survey the range of temperature is the least. On August 16, 1907, 
the bottom temperature off Gay Head was 57.2° F. (1634 fathoms) and 59.2° (1134 
fathoms), off Sow and Pigs 60.1° (10/4 fathoms), and in Vineyard Sound between these 
two points 55° (1734 fathoms); the surface temperature at these stations was from 3° to 
5° higher. On November 12, 1907, the bottom temperature off Gay Head was 51.9° 
(1014 fathoms), off Sow and Pigs also 51.9° (8 fathoms), and in Vineyard Sound between 
these points 52° (18 fathoms); the surface temperature at these points was about 1° 
lower. On March 20, 1908, the bottom temperature off Gay Head was 36.6° (8 fathoms), 
off Sow and Pigs 36.6° (5 fathoms), and in Vineyard Sound between these two points 
37.4° (18 fathoms); the surface temperatures being almost the same. On June 6, 1908, 
the bottom temperature off Gay Head was 57.6° (1214 fathoms), off Sow and Pigs 55.1° 
(7% fathoms), and on June 5 in Vineyard Sound between these two points 53.3° (18 
fathoms); the surface temperature at these points was then from 1° to 3° higher. These 
data are presented in tabular form below, the surface temperature being given above 
the line and the bottom temperature below. 
Aug. 16, 1907. Nov. 12, 1907. Mar. 20, 1908. June 5-6, 1908. 
x8, (x6 fath.) 
57-2 ° ° 
OfiiGay, Head's. 23.2 2stac ben seetenee oases Sante 56.8), = (xaté oth) 
62..4° as bath.) 51.9° (10% fath.)| 36. 6° (8 fath.) = (une) 
59-2 
Of SowaandyPigss.s:.cc- 0s. cova nee eee 63- 2 (10% fath.) sre? 2° (8 fath.) 36: =: (5 fath.) er = (7%4_ fath.) 
60. 1 51-9” 36. 55-1 (June 6) 
Between Gay Head and Sow and Pigs....... 60. 3° (1734 fath.) 512° (18 fath.) 36. 7° (18 fath.) ; (18 fath.) 
55 52 37-4 ER (June s) 
