KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 47. N:o I. il 



always shift, and that the local faunas are subjected to great variations. In a pre- 

 vious paper I have treated these questions 1 in a morc complete tnanner. 



Moreover, considering that the preceding account concerns the conditions of life 

 of the larvse within the fjords, how vvould the conditions be in the open sea? The 

 ansvver must be: the transport by currents leads to the ruin and destruetion of whole 

 generations. 



As the object of the present paper is to determine whether it is possible for 

 larvse of marine shallow-water animals to be transported by currents from polar-circle 

 to polar-circle, or not, I find occasion to quote some accounts of distinguished scienl ific 

 men, which confirm my views that the struggle for existence in the oceans is very 

 härd, much harder indeed, than can be endured by a larva of a shallow-water animal. 



Thus Murray 2 relätes: »Where cold and warm currents meet at the surface 

 of the oceans, there is a rise of temperature for the animals of the cold currents, 

 and a fall of temperatur for the animals of the warm currents, which results in a 

 plentiful destruetion of organisms. The tow-net collections during the Challenger 

 expedition gave frequent illustrations of this fact by the dead animals collected in 

 such positions off the coasts of North America, off the Cape of Good Hope, in the 

 North Pacific and elsewhere. . . . This destruetion of life is not limited to minute 

 pelagic organisms, but occasionally affects animals which live at the bottom of the 

 sea. Some remarkable instances of this kind have been observed between depths of 

 50 and 100 fathoms of the eastern coast of the United States.» 



In 1896 Goode and Bean 3 report: »that in 1880 and 1881 the 'Fish Hawk' 

 took tile fish (Lopholatilus chamceleonticeps) on several occasions at depths of from 

 70 to 134 fathoms. ... In the months of Mars and April, 1882, vessels arriving at 

 Philadelphia, New- York and Boston reported having passed large numbers of dead 

 or dying fish scattered över an area of many miles, and from descriptions and the 

 occasional specimens brought in, it was evident that the great majority of these were 

 tile fish. . . . Computations made by Capt. I. W. Collins seemed to indicate that an 

 area of from 5,000 to 7,500 square statute miles was so thickly covered with dead 

 or dying fish that their number must have exceeded the enormous number of one 

 billion. Since there were no signs of a disease, and no parasites found in the fish 

 brought in for examination, their death could not have been brought about by either 

 of these causes; and many conjectures were made as to the reason of this wholesale 

 destruetion of deep-water fishes, such as would ordinarily be unaffected by conditions 

 prevailing at the surface, submarine volcanoes, heat, cold, and poisonous gases being 

 variously brought forward to account for the loss of life. . . . The temperature in- 

 vestigations made by Col. Mc Donald have been carefully discussed by him, and lie 

 is convinced that the destruetion of Lopholatilus was due to climatic causes.» 



1 Om utvecklingen af Sveriges zool. hafsstation Kristineberg och om djurlifvet i angränsande haf och 

 fjordar. Arkiv för Zoologi. Stockholm 1907. 



3 On the annual range of temperature in the surface water of the ocean and its relation to other oceano- 

 graphical phenomena. — The Gcograplucal Journal. London 1898. 



3 Oceanic ichthyology. — Mem. Mus. Comp. Anat. Vol. XXII. Cambridge 1896, p. 285—288. 



