642 



BIOLOGY OF THE SEAS OF THE U.S.S.R. 



/935 ~ffll 



100 S00 300 Ш 500 600 700 



Fig. 302b. Alterations of food correla- 

 tions of benthos-feeding fish of the 

 Caspian Sea from 1935 to 1941 (Schory- 

 gin). The intensity of food correlation 

 between rival pairs of species of fish 

 during the period examined is given in 

 circles as indices of magnitude. The 

 diagonal line corresponds to the posi- 

 tion of points when food correlations 

 remain permanent. 



о го <ta 6o во wo /го /4o /во /во гоо гго гйо гео гдо 



Fig. 302с. Same as Fig 302в for the period 1941 to 1949 

 (Birstein). 



