326 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Eight specimens of tilefish were taken by the Grampus in 1892, as indicated in 
the following table : 
Depth. 
40 04 00 
40 01 00 
40 02 00 
40 06 30 
40 06 00 
39 57 00 
40 01 00 
38 09 00 
38 25 00 
38 40 00 
70 27 00 
70 35 00 
70 38 00 
72 34 30 
72 28 00 
72 22 30 
72 27 30 
72 11 00 
73 55 00 
73 36 00 
72 58 00 
72 58 00 
72 45 00 
Xo.of 
tilefish. 
Weight. 
Lbs. 
1 
7 
1 
13 
3 
(b 
(?) 
2 
(?) 
Two of the stations (4 and 9) at which tilefish were taken are located on the 
original tilefish ground, at a point that had not been tested by either the Fish Haivlc 
or the Albatross, although the latter vessel in 1883 dredged within 7 miles of this 
spot, and in 1886 Captain Collins used trawls still nearer. The other stations at which 
the fish were found (19, 20, and 24) were considerably farther to the west, a locality 
that had been examined by the Albatross in 1883 and again in 1884. This locality, 
near the great snbmarine channel which cuts through the continental shelf from the 
mouth of the Hudson to the deep water underlying the Gulf Stream, was the seat of 
continued investigations during the following season.* 
The reasons for the movements of the Grampus in 1892 and 1893 are stated in a communication 
from Professor Libhey, bearing date April 3, 1899, in reply to certain questions which I had asked. 
“With regard to the capture of the tilefish (in 1892), to the westward of the positions where my 
observations had been made, I would say that the facts which have been published cover only a small 
amount of the items which are to be derived from a careful and systematic study of the temperature 
observations. When in Washington, at the time of the conference with Colonel McDonald, I told 
him that if the tilefish were of fi tropical form he might expect to find the fish that year, provided the 
conditions I anticipated were fulfilled at one of two points, and I marked the positions on a map in 
his office — one of them being off the Delaware capes, the other south of Martha’s Vineyard — and I 
gave as my reasons that I felt quite sure that the break or depression in the continental edge, repre- 
senting the bed of the Hudson River, was of such a character and depth as to prevent the tilefish 
from crossing it, unless the high temperature had proceeded far enough inland, or in toward the land, 
to make a connection across the upper part of this depression. If you will examine the charts of the 
Coast Survey you will find that there is a somewhat remarkable depression on the edge of the conti- 
nental platform to the southeast of the mouth of the Hudson River. It was my idea that a band of 
warm waters moving in from the southeast would touch this platform ; but as the tilefish apparently 
was a bottom fish, the migration of the school would stop if the temperature variations did not touch 
the bottom clear around this depression. If such were the case, the fish would be found oif the 
Delaware capes only; but if the connection had been made the fish would probably be found in 
both places. * * * * * * 
“When we succeeded in finding the fish in the area where my observations had been made, I 
immediately suggested to Colonel McDonald that we follow up the edge of the continental platform. 
