The Migration of Fishes. 35 
the temperatures no doubt exist. The hundred-fathom curve 
is distant about 4o miles from the point of the Cape, and the 
average summer limits of the Gulf Stream, as laid down upon 
the British Admiralty charts, extend nearly to this curve. 
The observations made at Wilmington, situated as it. is in a 
bend of the coast, at least too miles from the summer limits 
of the Gulf Stream, and at the mouth of a river which rises 
200 miles away in the elevated central portion of North Car- 
olina, can hardly be taken as criteria of the temperature of 
Cape Hatteras. This is still more unfortunate from the fact 
that the movements of the menhaden, blue-fish, sea-trout, and 
other warm-water species, are very peculiar at this point. It 
will be strange if the monthly mean of water temperature for 
Cape Hatteras, in December, and perhaps January, does not 
prove to be more than 50 deg. Savannah is at least 120 
miles from the Gulf Stream, and its means for December and 
January, 1876-1877, as well as those of Charleston, are below 
50 deg. Charleston water appears to be uniformly warmest. 
In 1874, December, in Charleston, averaged 48 deg. 8m.; in 
1875, January averaged 50 deg. 2m. The movements of the 
menhaden in this region have not been observed, but since in 
the north it is not more hardy than the shad, and since the 
shad do not venture into the Georgia and Carolina rivers in 
December, it is safe to predict that the habits of the menha- 
den are similar. Jacksonville, Fla. is the only point on the 
coast from which there are observations showing a tempera- 
ture uniformly above 51 deg., and here menhaden remain 
throughout the winter. 
IllLJ MAXIMUM LIMITS. 
On the coast of Eastern Maine we are told that the men- 
haden schools keep passing to the eastward until about the 
