THE DEPOSITS OF THE SEA-BOTTOM. 



65 



reason to suppose that they can be carried far by the current; if upon the whole such a transport 

 takes place, it must be where the water is less deep, and the movement so strong, that finer particles 

 cannot be deposited, and this is not the case with any of the deep-sea deposits of the expedition. 

 Among the factors that are of importance with regard to Jhe deposition of the organisms, are of 

 course principally to be named the temperature, salinity, and depth; it is, however, almost impossible 

 to distinguish these factors from each other in the individual cases. The mass of organic material 

 as a whole cannot be taken as a measure to show, whether larger or smaller masses of organisms are 

 deposited on the locality in question; the fact is that this mass is principally dependent on the mass 

 of mineral material; as this latter is deposited most abundantly closest to the land, but farther out 

 only to a considerable smaller degree, the consequence is, that the organisms will make a continually 

 larger percentage of the deposit, the farther we go from the land; but from this we can draw no 

 conclusion at all with regard to the absolute quantity in which they are deposited, which quantity 

 can scarcely be measured by any means whatever. Another matter is whether some conclusions may 

 be drawn from the ratio of the individual organisms in the specimens. 



I. The Foraminifera. 



Among all the organisms, the Foraminifera, I think, play the most important part on account 

 of the immense masses in which they are found in the specimens. The Coccoliths, to be sure, are 

 present in a many times larger number, but on account of their smallness they are not of so great 

 importance. As a rule the Foraminifera may be supposed to be far more than half of the carbonate 

 of lime in the specimens; great part of the rest consists of amorphous lime-ooze with numerous Cocco- 

 liths and Coccospheres. The higher organisms with calcareous shells are only found in small numbers 

 at a greater distance from land, whereas they are more numerous near land, and in some cases, per- 

 haps, may form the greater part of the small percentage of carbonate of lime found in the Gray deep- 

 sea clay. For practical reasons the Foraminifera have been classed in two divisions according to their 

 being larger or smaller than o-^ mm . In the first class, which is found in the part of the specimen that 

 has been sifted, most frequently together with proportionally very small masses of mineral material, 

 each individual is examined by means of the magnifying glass, and classified into the different groups; 

 the smaller ones are found by placing some of the sifted substance under a microscope. If small 

 Foraminifera be very scarce in the specimen, it may happen that none are seen in the part under the 

 microscope; but then it is also proved that they are only found in minimally small numbers in the 

 bottom-specimen in question, and I have not thought it necessary to search for the single individuals 

 by the special methods for the isolating of Foraminifera, as by the present examination the essential 

 thing is to point out what is of most importance in the specimens. The two classes of Foraminifera 

 are seen to differ very much from each other; while the smaller ones are almost exclusively of the 

 genus Globigerina, this genus is only exceptionally found among the larger ones, where other genera, 

 different in the different specimens, are most conspicuous. 



a. Foraminifera under o-5 ram were found in the specimens as shown by the following table: 



Station 2; 2-85 per ct. CaC0 3 ; one Globigerina. 



Station 3; 3-64 per ct. CaC0 3 ; a few Globigerinse. 



The Ingolf-Expedition. I. 3, 9 



