The Foraminifera of the Canadian Arctic Expedition, 1913-18. 



By JOSEPH A. CUSHMAN. 

 (With one plate.) 



The bottom samples collected by the Canadian Arctic Expedition by Mr. 

 Frits Johansen were sent to me for examination and report. The area covered 

 by the material is an interesting one, from which practically no records of 

 foraminifera are available. The actual amount of material sent me was very 

 small indeed, but careful searching has given a number of species. Most of 

 these are of service in checking the work of Awerinzew on the Siberian Arctic, 

 and of Kiaer on the American and European Arctic. In this way it rounds out 

 the circumpolar distribution of certain species, such as Hyperammina subnodosa r 

 which was not found by Kiaer in the American Arctic, but which is abundant 

 north of Siberia. The Canadian Arctic material has this species as its most 

 abundant form. 



The whole assemblage seems to call renewed attention to the fact that many 

 species of foraminifera are limited in their distribution to conditions of tempe- 

 rature, especially certain species, such as Polystomella arctica, are limited to the 

 circumpolar area, with certain localized extensions southward. Others, while 

 abundant in the Arctic, are now found in the Antarctic, and in the deep eold 

 waters of the ocean basins between, a distribution known from other invertebrate 

 groups as well. 



Other species apparently of world-wide distribution have wide differences 

 in different areas and, when a considerable series is available for study, it will 

 probably be found that several distinct species or varieties have been included 

 under one name. The tendency has been too much to ignore the various 

 differences developed, and to place under one name different things from widely 

 separated areas. Again, there has been a tendency to broaden the original 

 characters of a species until it may now take in a wide range of forms, the real 

 relations of which are obscured by such a method. Where a species is repre- 

 sented by abundant specimens, the striking thing is always the great uniformity 

 rather than the wide variation which might be expected, but which does not 

 occur. Most of the variablity can be directly traced to different stages in the 

 life-history, either developmental characters, or to the alternation of generations 

 where both microspheric and melagospheric forms occur. With these taken 

 into consideration, the amount of variation will usually be found to be sur- 

 prisingly small. 



If real progress is to be made in solving the distributional problems of our 

 foraminiferal fauna, a close study must be made of differences wherever they 

 occur. Such a study will undoubtedly lead to a greater refinement in systematic 

 work on the group. 



STATIONS FROM WHICH MATERIAL WAS EXAMINED WITH SPECIES OF FORAMINI- 

 FERA AT EACH STATION. 



13Z. Bering Sea, Alaska. 54 24' N.; 160 55' W.; 57 fathoms. July 1, 

 1913. A small amount of rounded sand grains, no foraminifera. 



IQd. Bering Sea, Alaska. 59 17' N.; 165 39' W.; 13 fathoms. July 5, 

 1913. A small amount of rounded sand grains, no foraminifera. 



16/. Bering Sea, Alaska. 59 34' N.; 167 48' W.; 13 fathoms. July 5, 

 1913. A small amount of fine rounded sand grains, no foraminifera. 



160. Same station as preceding, no foraminifera. 



20 b-c. Grantley harbour (Port Clarence), Alaska; 2-3 fathoms. July 30^ 



48357 U 



