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593.12 
E 
On the Distribution of the Pelagic Foraminifera at 
the Surface and on the Floor of the Ocean. 
hee pelagic Foraminifera play a most important role in the 
economy of the present ocean, as well as in the geological 
history of our planet. Living specimens of these pelagic Protozoa 
are distributed everywhere in the surface waters of the open ocean, 
about fifteen or twenty species being met with in the surface waters 
of the tropics, and one or two dwarfed species are captured among 
the floating icebergs of the Arctic and Antarctic regions. The dead 
shells of these Foraminifera make up by far the larger part of the 
carbonate of lime present in the deep-sea deposits known as Pteropod 
and Globigerina Oozes, which cover about 50,000,000 square miles 
of the ocean’s bed. In addition, they make up the major part of 
the carbonate of lime present in the other deep-sea deposits, such as 
Diatom Ooze, Radiolarian Ooze, Red Clay, and the deeper terrigenous 
deposits which are laid down in close proximity to continents and 
oceanic islands. Indeed, it may be said that, taken as a whole, 
nine-tenths of the carbonate of lime in marine deposits from depths 
greater than one hundred fathoms is derived from the dead shells of 
the pelagic Foraminifera. 
When the Challenger set out on her cruise around the world, 
all the naturalists of the expedition believed that the habitat of the 
Globigerinae was on the sea-bed in deep water. This opinion was 
held by Wallich, Carpenter,? and Wyville Thomson? Gwyn 
Jeffreys,t however, took another view; he regarded the Globigerinae 
as surface organisms, and the Globigerina Ooze as made up of dead 
shells which had fallen:to the bottom from the surface waters. The 
fact that M‘Donald® and Major Owen® had captured several species 
of these Foraminifera in tow-nets at the sea-surface appears to have 
1The North Atlantic Sea-bed. London, 1862; also Deep-Sea Researches on the 
Biology of Globigerina. London, 1876. 
2 Proc. Roy. Soc., vol. xxiii. p. 234. 1875. 
3 Proc. Roy. Soc., vol. xxiii. p. 32. 1874. 
4 Proc. Roy. Soc., vol. xviii. p. 443. 1869. 
5 See Huxley’s Appendix to Dayman’s Report on Deep-Sea Soundings in the North 
Atlantic made in H.M.S. Cyclops in June and July 1857. London, published by the 
Admiralty, 1858. 
§ Journ. Linn. Soc. Lond., vol. ix. (Zool.), p. 147. 1866, 
B 
