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This may perhaps be accounted for by our not having struck their belt of depth with the tow-net; or it is possible that when we found it on the 11th of February the bottom deposit was really shifted a little to the south by the warm current, the excessively fine flocculent débris of the Diatoms taking a certain time to sink.
We never have been able to detect, in any of the large number of Globigerinoe which we have examined, the least trace of pseudopodia, or any extension, in any form, of the sarcode beyond the shell. "In specimens taken with the tow-net the spines are very usually absent; but that is probably on account of their extreme tenuity; they are broken off by the slightest touch.
No animal life observed. Lower Clark's tow-net with 566 fathoms of wire, and hoist it up at two and a half miles an hour by walking across the floe with the wire. Result rather meagre jelly-fish and some fish larvae. Exercise dogs in sledge teams. The young dogs, under Crean's care, pull as well, though not so strongly, as the best team in the pack.
A tow-net is filled with diatoms in a very short space of time, showing that the floating plant life is many times richer than that of temperate or tropic seas. These diatoms mostly consist of three or four well-known species. In turn they afford food for creatures great and small: the crab-eater or white seal, the penguins, the Antarctic and snowy petrel, and an unknown number of fish.
Murray has combined with a careful examination of the soundings a constant use of the tow-net, usually at the surface, but also at depths of from ten to one hundred fathoms; and he finds the closest relation to exist between the surface fauna of any particular locality and the deposit which is taking place at the bottom.
Huxley was not so well situated as either Darwin, the well-to-do amateur who was naturalist to the expedition, or Hooker, the son of a distinguished botanist, receiving many privileges from his father's friend, Captain Ross, while officially he was but an assistant-surgeon and second naturalist. Huxley had neither friends nor influence beyond the simple recommendation of "old John" Richardson. Macgillivray, the naturalist, and the Captain himself had scientific interests, but not so the other officers, who disliked seeing the decks messed by the contents of the tow-net. Yet they were "as good fellows as sailors ought to be, and generally are," though they did not understand why he should be so zealous in pursuit of the objects which his friends the middies christened "Buffons," after his volume of the Suites
In all seas, from the equator to the polar ice, the tow-net contains Globigerinoe. They are more abundant and of a larger size in warmer seas; several varieties, attaining a large size and presenting marked varietal characters, are found in the intertropical area of the Atlantic.
By this time the ship left Callao for Honolulu, Manila, Hong Kong, and, as the Challenger had not crossed the Pacific Ocean in these directions, we made several soundings and deep-sea thermometrical measurements from Callao to Honolulu. With the thermometer wire has always been sent down a tow-net which opens and closes automatically, also invented by Captain Palumbo.
On the 4th of February, in lat. 52°, 29' S., long., 71° 36" E., a little to the north of the Heard Islands, the tow-net, dragging a few fathoms below the surface, came up nearly filled with a pale yellow gelatinous mass. This was found to consist entirely of Diatoms of the same species as those found at the bottom.
In the latitude of Kerguelen they are less numerous and smaller, while further south they are still more dwarfed, and only one variety, the typical Globigerina bulloides, is represented. The living Globigerinoe from the tow-net are singularly different in appearance from the dead shells we find at the bottom.
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