GENERAL BIOLOGY 



m 



which have also a bottom stage on the coast banks. In August 

 1900 their distribution was identical with that of the pelagic 

 cod fry, and was limited by curve III. in chart, Fig. 523. 

 Similar instances might be quoted in profusion, especially from 

 recent Danish and Norwegian investigations. Of special 

 interest is the great number of observations of larvae and young 

 fish drifting from the Atlantic coast banks off the west coast of 

 Scotland into the North Sea and the Norwegian Sea (compare 

 the drift of Salpse). 



We will now proceed to review our knowledge as to the 



Fig. 525.— Relative numbers of the earliest Bottom-Stages of Gadus virens 



AND G. CALLARIAS AROUND ICELAND IN THE SUMMER OF I904. (P^rom Schmidt.) 



conditions of the Atlantic, referring, for want of space, mainly 

 to our own investigations. 



It is not an easy matter to examine the reproduction of 

 animals in the open ocean. Very few studies have, there- 

 fore, been made on the development of the oceanic fishes, 

 and little is known as to their characters in early stages. 

 Valuable information has been gathered and drawings have been 

 made, especially by Giinther and by Danish naturalists, Lutken 

 and others, but complete series, showing the development of the 

 species, are only available for a very limited number of species. 

 Every expedition must, therefore, in the present state of our 

 knowledge, make a laborious systematic study of the collections 



