SUMMARY OF RESULTS 



In the foregoing Report, 64 species and varieties of Foraminifera and 11 species 

 of Ostracoda are described or recorded. Among the Foraminifera the following are 

 new : 



' Miliolina subrotunda, Mont, sp., var. striata; 

 ,, oblonga, Mont, sp., var. arenacea; 

 Reophax longlscatiformis; 



„ murrayana; and 

 Nonionina scapha, F. and M. sp., var. bradlL 



There is also a new species of the Ostracoda, viz. Cythere davlsl. 



A notable feature in the present foraminiferal fauna is the large number of species 

 which are undoubtedly common to the cold areas of the north and south polar regions. 

 Amongst these may be cited : Saccammina sphcerica, Haplophragmium canariense, 

 H. latidorsatum, Virgidina schreibersiana, Lagena apiculata, L. marginata, Polymorphina 

 oblonga, Uvigerina pygmcea, Globigerina bulloides, G. inflate, Truncatulina lobatula, 

 Nonionina depressula, N. stelligera, and Polystomella crispa. 



The Ostracoda here recorded are almost peculiarly a southern oceanic fauna ; a 

 marked exception is Cytherura rudis, already known from Spitzbergen, Greenland, and 

 other localities in the Far North. One or two species, however, have a somewhat ex- 

 tensive range, as will be seen on referring to the distributional notes with each species. 



Of the bipolar species of Foraminifera, Saccammina sphcerica is perhaps the most inter- 

 esting, since it has been almost exclusively obtained from stations in high latitudes, and 

 only twice in low latitudes, in the North Pacific and South Atlantic, both in deep water. 

 In this, as in other species of bipolar Foraminifera, the following fact is clearly brought 

 out : that these tiny organisms, born and bred in the richer, shallow mud-zones of 

 high latitudes, sink into deeper water areas when spreading out through the tropical 

 and inter -tropical seas, and again graduate into shallower marine conditions as they 

 approach the polar regions. The shallow-water foraminiferal fauna of warmer latitudes, 

 on the other hand, show, broadly speaking, a restricted field. In the two recorded 

 occurrences of Saccammina sphcerica in inter-tropical seas, it will be noticed that the 

 stations are both situated in main axes of abyssal troughs trending north and south. 



The existence of a selective instinct implanted in the Foraminifera is here given 

 further proof in the case of Reophax spiculifera ; for, although living side by side with 

 R. dentaliniformis, a form whose test is an agglutination of comparatively coarse, 

 angular sand grains, it rejects this material in favour of short, siliceous sponge spicules, 

 with which awkward material it constructs fairly neat, long, funnel-shaped chambers, 

 resembling in shape the straw covers of wine bottles. 



In the following Table of Bathymetrical Distribution, it will be seen how remarkable 

 a feature is the segregation of many species of Foraminifera within a bathymetrical 

 zone or series of depths within certain limits. This peculiarity of the fauna may, of 

 course, be largely induced by the nature of the sea bottom in supplying suitable food 

 and building material. 



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