THE BEGINNINGS OF LIFE. 123 



to throw a great additional interest over this oceanic 

 Moner, which, it is now believed, must have existed 

 far back in geologic time, and must have played a 

 most important part, by the accumulation of its in- 

 organic remains, in the formation of ancient chalk 

 strata, just as it is now being instrumental in the de- 

 position of another chalk stratum in the bottom of our 

 great Atlantic Ocean 1 . Captain Dayman was much 



1 Referring to this subject in an interesting lecture ' On a Piece of 

 Chalk.' (' Macmillan's Mag.' Sep. 1868, p. 399), Prof. Huxley says: 

 ' The result of all these operations is that we know the contours and 

 nature of the surface-soil covered by the North Atlantic for a distance 

 of 1,700 miles from east to west, as well as we know that of any part of 

 the dry land. ... It is a prodigious plain one of the widest and most 

 even plains in the world. If the sea were drained off, you might drive 

 a waggon all the way from Valentia, on the west coast of Ireland, to 

 Trinity Bay in Newfoundland. . . . From Valentia the road would lie 

 down hill for about 200 miles to the point at which the bottom is now 

 covered by 1,700 fathoms of sea water. Then would come the central 

 plain more than a thousand miles wide, the inequalities of the surface of 

 which would be hardly perceptible, though the depth of water upon it 

 now varies from 10,000 to 15,000 feet; and there are places in which 

 Mont Blanc might be sunk without showing its peak above water. 

 Beyond this, the ascent on the American side commences, and gradually 

 leads, for about 300 miles, to the Newfoundland shore. . . . Almost the 

 whole of the bottom of this central plain (which extends for many 

 hundred miles in a north and south direction) is covered by a fine mud, 

 which, when brought to the surface, dries into a greyish-white, friable 

 substance. You can write with this on a black board, if you are so 

 inclined, and to the eye it is quite like very soft, greyish chalk. Examined 

 chemically, it proves to be composed almost wholly of carbonate of lime ; 

 and if you make a section of it in the same way as that of the piece of 

 chalk was made, and view it with the microscope, it presents innume- 

 rable Globigerina, embedded in a granular matrix. . . . Thus this deep 

 sea mud is substantially chalk. I say substantially, because there are 



