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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.
This sea ran, like an early northern Mediterranean, right across the face of Central Europe; and on its bottom was deposited the soft ooze of globigerina shells and siliceous sponge skeletons which has now hardened into chalk and flint.
But some of these remains prove the existence of reptiles of vast size in the chalk sea. These lived their time, and had their ancestors and descendants, which assuredly implies time, reptiles being of slow growth. There is more curious evidence, again, that the process of covering up, or, in other words, the deposit of Globigerina skeletons, did not go on very fast.
In a word, it is certain that these animals have lived and died when the place which they now occupy was the surface of as much of the chalk as had then been deposited; and that each has been covered up by the layer of Globigerina mud, upon which the creatures imbedded a little higher up have, in like manner, lived and died.
We gazed long at these beautiful effects. The ship made through leads during the night; morning found us pretty well at the end of the open water. We stopped to water ship from a nice hummocky floe. We made about 8 tons of water. Rennick took a sounding, 1960 fathoms; the tube brought up two small lumps of volcanic lava with the usual globigerina ooze.
Thomson and Dr. And I agree with Dr. If the word "chalk" is to be used as a stratigraphical term and restricted to Globigerina mud deposited during the Cretaceous epoch, of course it is improper to call the precisely similar mud of more recent date, chalk.
The first four stations on this section, at depths from 1,525 to 2,220 fathoms, show Globigerina ooze. From the last of these, which is about 300 miles from Teneriffe, the depth gradually increases to 2,740 fathoms at 500, and 2,950 fathoms at 750 miles from Teneriffe.
However this may be, the explanation thus offered of the presence of the fine mud, and of the absence of organisms which ordinarily live at the bottom, does not account for the absence of the skeletons of the organisms which undoubtedly abound at the surface of the Mediterranean; and it would seem to have no application to the remarkable fact discovered by the Challenger, that in the open Atlantic and Pacific Oceans, in the midst of the great intermediate zone, and thousands of miles away from the embouchure of any river, the sea-bottom, at depths approaching to and beyond 3,000 fathoms, no longer consists of Globigerina ooze, but of an excessively fine red clay.
If, on the other hand, it is to be used as a mineralogical term, I do not see how the modern and the ancient chalks are to be separated and, looking at the matter geographically, I see no reason to doubt that a boring rod driven from the surface of the mud which forms the floor of the mid-Atlantic would pass through one continuous mass of Globigerina mud, first of modern, then of tertiary, and then of mesozoic date; the "chalks" of different depths and ages being distinguished merely by the different forms of other organisms associated with the Globigerinoe.
Nor can the presence of the soft parts of the body in the shells which form the Globigerina ooze, and the fact, if it be one, that animals living at the bottom use them as food, be considered as conclusive evidence that the Globigerinoe live at the bottom.
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