q 
THE DEPTH AND MARINE DEPOSITS OF THE PACIFIC OCEAN. 15 
nodules runs in a southeasterly direction to about 100° W. long., and 5° 
south of the equator where it runs nearly due east off Aguja Point, its 
eastern line then runs south, parallel to the South American coast. The 
southern limit of the nodules as here given (PI. 3) is probably not its south- 
ernmost limit, as the ‘Challenger’ obtained manganese nodules a long way 
south in the latitude of Valparaiso; but nothing is known of the character 
of the bottom on the area intervening between the lines of the ‘ Albatross’ 
and ‘ Challenger.’ The western and northern and eastern limits of the Radi- 
olarian ooze (Pl. 3) indicate a great tract partly covering the area of 
manganese nodules. 
“To the west of the Radiolarian ooze area lies a great tract of Globiger- 
ina ooze; it is east of the Marquesas and of the Paumotus and extends north 
some way into Moser Basin (PI. 3). 
“ Diatoms are found in a very wide belt reaching from the equator to 
nearly the general latitude of 15° S., in some localities south and west of 
Aguja Point, as well as others. Close to the South American coast they 
occur in sufficient quantities to have formed siliceous earth. It will be noted 
that the belt where diatoms occur is entirely within the influence of the . 
western and northern set of the Humboldt current, and that while diatoms 
are found in great abundance in an area near the equator, yet they have 
undoubtedly been brought north by the Humboldt current from more 
southern latitudes than those explored by the ‘ Albatross,’ and have been 
spread westward by the prevailing southeast trades of the belt where they 
are found (PI. 4). .... 
“ Hauls of the trawl made off the Galapagos and at the western ex- 
tremity of our lines off Aguja Point brought us within the area of the 
manganese nodules, with its Radiolarian ooze mud, Cetacean ear-bones, and 
beaks of Cephalopods; nothing could stand the damaging work of these 
nodules in grinding to pieces all the animal life the trawl may have obtained 
(Pl. 3). Down to a depth of 2200 fathoms or so the bottom was constituted 
of Globigerina ooze, its character being more or less hidden when near the 
coast by the amount of detrital matter and terrigenous deposits which have 
drifted out to sea. 
“North of the Galapagos, as in the 1891 expedition, we found vegetable 
matter at nearly all the stations, and between the Galapagos and Callao such 
material was not uncommon in the trawl. 
“Beyond the line of 2200 fathoms dead radiolarians become quite abun- 
