THE CASPIAN SEA 



577 



SOUTHERN CASPIAN WESTERN COAST 

 SOUTHERN CASPIAN EASTERN COAST 

 CENTRAL CASPIAN EASTERN COAST 

 CENTRAL CASPIAN WESTERN COAST 



— — %OCCUR«ENCE 



MEAN BIOMASS 



$8 \'9 .. 



03 Жг~3>* 



400 



300 



ZOO 



100 



u ats wi zj& i о 



10 20 30 40 50 60 70 80™™ "> 

 В 



IT 



53 



Ш STATIONS WITH LIVE MYTIIASTW 



| | STATIONS WITH OEAD MYTILASTE* 

 DEAD BIVALVES 



49 



£T 36 



18 18 



21 



1 

 '■ 0-10 10-20 ZMO 3040 iuTo 5040 60To 70-80 



Fig. 273. Mytilaster lineatus biomass (g/m 2 ). / In Central and Southern Caspian 



according to the years ; II Distribution with depth ; A Occurrence (% stations) and 



mean biomass (g/m 2 ); В Ratio between the living and the dead Mytilaster 



(Brotzkaya and Netzengevitch). 



Caspian Sea ; it has penetrated into the northern part and in particular into 

 Mertvyi Kultuk. M. saliens is adapted mainly to the western shore, where it 

 lives with M. auratus. On the Turkmen coast M. saliens is more numerous 

 than M. auratus. 



Finally, in 1939 and 1940, Nereis and Syndesmya ovata were brought from 

 the Sea of Azov into the Caspian Sea for acclimatization in order to increase 

 food resources for commercial fish.* Sixty-one thousand specimens in all of 

 Nereis and 18,000 specimens of Syndesmya ovata were put overboard in 

 different places of the Caspian Sea (L. A. Zenkevitch, Ya. Birstein and A. Kar- 

 pevitch, 1945). 



In the autumn of 1944 N. Spassky (1945) recorded for the first time 



* In the course of the transplantation of Nereis into the Caspian Sea there was a 

 theory that the transplanted species was Nereis succinea. 



Some time later this belief altered and doubts arose. The first one to express doubt 

 was Dr. Joel W. Hedgpeth (1957), who in his 'Treatise' published some critical notes 

 referring to my paper on the Caspian Sea. Presently material on the Nereis from the 

 Caspian Sea was forwarded to the prominent specialist working with the Polychaeta, 

 Olga Hartman. She classified this species as Nereis diversicolor (1960). The careful 

 examination of Nereis coming from the Caspian Sea (V. Chlebovitsch, 1962) has con- 

 firmed the wide-range distribution of this species throughout various seas, whereas 

 Nereis succinea was not discovered. 



2o 



