TETRAPLATIA VOLITANS 133 



So far there are no records either from the Arctic or from the Red Sea. It would be interesting to 

 I<^now whether Tetraplatia penetrates into the Arctic basin and also whether it can tolerate the high 

 saUnity of the Red Sea. 



Fig. I. The distribution of Tetraplatia volitans in the North Atlantic. H.M.S. 'Research': open circle with a central dot; 

 R.R.S. 'Discovery IF: black circles in Atlantic; F.R.V. 'Explorer': half circle filled-in; previous records in the Mediter- 

 ranean : black circles. 



