1902-3.] The Pal^ochemistry of the Ocean. 553 



and the combination of this element with argillaceous matter at the 

 bottom of shallow portions of the sea began. As a result the amount 

 of potassium in sea water became stationary. At the same time the 

 removal of calcium on a larger scale than obtained in the preceding 

 period commenced and this checked the increase of calcium salts. 



The first forms of life in the primeval ocean were undoubtedly 

 unicellular, and they were probably also organisms which presented 

 features intermediate between those of the vegetable kingdom on the one 

 hand, and those of the animal kingdom on the other. These forms must 

 have persisted for a period of unknown but very great duration, for in 

 them developed not only a nucleus but also the capacity on the part o' 

 the latter to divide in the remarkable and complicated manner illustra- 

 tive of karyokinesis, and which is characteristic now of the cells of both 

 kingdoms. This process of division, so alike in its main features in 

 animal and vegetable cells, must have become fixed before specialization 

 had gone so far as to evolve both animal and vegetable types, for, had it 

 been otherwise, there would have been greater differences in the pro- 

 cess in animal and vegetable forms. That the process has continued 

 practically unchanged in all the intervening millions of years shows how 

 deeply fixed in the organism this morphological habit has become, and, 

 therefore, the act of fixation must have taken an incredibly long period 

 of time during which the ocean was changing, not in the relative propor- 

 tions to each of the elements it contained, but in the absolute amounts 

 of these. 



During this long period, these organisms, neither distinctly animal 

 nor distinctly vegetable, exposed as they were to action of these 

 same elements, must have acquired a relation to them as fixed as the 

 karyokinetic process was becoming. Their protoplasm had established 

 all its normal processes in the presence of potassium, sodium, calcium, 

 and magnesium in certain proportions in sea water, and, after the lapse 

 of the long period of time required for the elaboration of the karyo- 

 kinetic method of division, these processes became unalterably depen- 

 dent on the presence of the elements in the proportions which then pre- 

 vailed. Without this fixed relation life could not continue, and when 

 specialization into animal and vegetable forms occurred this fixed relation 

 was transmitted to the forms of both kingdoms. How long these latter 

 forms remained unicellular cannot, of course, be surmised, for there are 

 no means of determining the length in time of this or any part of the 

 pre-Cambrian age, but that it was of very great duration can hardly be 

 questioned, and it must have strengthened the relation which obtained 

 between protoplasm on the one hand and the elements in certain pro- 



