SOILS AND MOSSES OF SPITSBERGEN. 455 
One new flagellate is described which does not seem to have been recorded 
elsewhere, and it is possible that some of the organisms which occurred in 
the cultures in too small numbers to be identifiable may have represented 
other new species. 
The ubiquity of these moss- and soil-dwellino- protozoa has an additional 
significance, since they have no means of avoiding the extremes of tempera- 
ture or of moisture to which they are exposed; Planktonic organisms can 
avoid extreme heat or cold by sinking to greater depths, and worms, many 
insects, etc., can similarly burrow to more equable layers if the surface of 
the soil becomes too hot or too cold except, of course, in regions where 
the sub-soil is frozen. But such vertical migrations of the land-living 
protozoa, if they take place at all, must be very much more restricted, 
and the wide distribution of these organisms must therefore indicate 
a wide range of tolerance of external conditions on the part of the 
organisms themselves or of their cysts (though resistant cysts are not at 
present known for all the creatures in question). There remains the possi- 
bility of the existence of physiological strains differing solely in their powers 
of resisting extreme conditions. This is, in fact, very probable, since many 
unpublished observations made in this laboratory have demonstrated the 
presence in tropical soils (Egypt, East Africa, West Indies, etc.) of species 
identical with some occurring in Spitsbergen, which therefore in natural 
conditions tolerate a wider range of temperatures than is possible in 
laboratory cultures. 
The identity of the protozoal fauna of Spitsbergen with that of temperate 
lands is strikingly paralleled by the observations made by Barthel (6) on the 
soil bacteria of Greenland. An examination of soils collected by the 
Rasmussen Expedition from Disko Is. (Lat. 70° N.), from Cape York (Lai 
76° N.), and from the extreme northern coast showed that these soils, just 
like ordinary European soils^ are capable of initiating the processes of 
nitrification, denitrification, ammonification, and fermentation of urea ; and 
though nitrogen fixation was not definitely proved, there was some evidence 
of its occurrence. These results would no doubt apply equally in the 
somewhat milder climate of Spitsbergen. Thus all the evidence at present 
available points to the qualitative identity of the microbiological activity 
of soils from Spitsbergen and from temperate lands. As to the quantitative 
aspects of the question, observations made on the spot would be essential. 
