16 BULLETIN OF THE 
45° curve at about the 350 fathom line, and the 40° curve at the 650 
fathom line, indicating a much larger body of warm water between 
Abingdon and Wenman (Plate XII. Fig. 1) than between Indefatigable 
and Bindloe, while farther south, near Chatham (Plate XI. Figs. 2, 3, 4), 
the upper belt of temperatures indicated are the coldest, the 60° curve 
being above the 50 fathom line. 
The temperatures were all taken during February, March, and April 
of 1891. The sections of the first lines, Panama to Cocos, to Malpelo, 
and back again to Panama, were taken during the last of February and 
the beginning of March; those from Galera Point and the Galapagos dur- 
ing the latter part of March and beginning of April; and the line from 
the Galapagos to Acapulco from the 3d of April to the 12th. 
The soundings and temperatures taken during our trip up the Gulf 
of California indicate free connection with the Pacific, (see the bottom 
temperatures of Stations 3424 to 3437 in the Gulf of California, page 8, 
and Hy. 2635, page 17, the deeper stations having practically the same 
temperature as the oceanic temperatures off Acapulco,) the 1,500 fathom 
line sweeping across the opening of the gulf with a rapid rise to the 
1,000 fathom line running parallel to the two coasts, and a very flat 
bottom along the central part of the Gulf of California to the line where 
the 1,000 fathom curve cuts across the gulf off Topolobampo, the bottom 
rising again gradually along the centre of the gulf to the 500 fathom 
line, which extends north of Guaymas. The rapid decrease of the sur- 
face temperatures as well as that of the upper belt of water to 100 fath- 
oms, within the Gulf of California, is very marked. See the record, on 
page 8, of Stations 3424 to 3437, and Hy. 2635, page 17. 
The accompanying table shows the serial temperatures taken at the 
different Stations. The position is given in the list of Stations occupied, 
on pages 4 to 8. 
