TRANSACTIONS 



OF THE 



SOUTH AFKICAN PHILOSOPHICAL SOCIETY. 



Vol. XYII. 



THE OPISTHOBBANCHIATA OF SOUTH AFBICA. 



By E. Bergh, Copenhagen. 



(With fourteen Plates) 



The number of Opisthobranchiata hitherto known from the coast 

 of South Africa is very small. Krause described a Pleurobranchus 

 granulatus, Vayssiere a Pleurobranchcea capensis, Rang a Melibe 

 rosea, Stimpson a Tritonia pallida and a Triopa lucicla. 



The investigations of late years of the Cape Government, carried 

 out under the direction of Dr. Gilchrist, have considerably aug- 

 mented the number, and have furnished the material for the 

 following report. 



The East and South Coasts of South Africa are washed by a 

 prolongation of the great equatorial current from the Indian Ocean ; 

 the West, on the contrary, by the cold Antarctic current. Some- 

 times, however, it happens that the warm Agulhas current passes up 

 this side, while at other times the cold Antarctic current passes 

 further to the East.' 1 ' In general there is a marked difference 



* Gilchrist, " Observations on the Temperature and Salinity of the Sea around 

 the Cape Peninsula." Mar. Inv. I., 1902, pp. 181-216. 



Gilchrist, " Currents on the South African Coast, as Indicated by the Course of 

 Drift Bottles," part ii. 1904, pp. 155-166. 



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