RV Platessa tagged plaice were released off the Cumberland coast, using the RV "Platessa" during 1949 and 1950. In August 1951 echo-sounder traces were obtained over a wide area off Whitby by the RV 'Platessa', using a Marconi sounder. They were found to occur at a depth corresponding to that of a sharp thermocline, and small whiting about 3 in. in length, large Medusae, herring and sandeel larvæ were caught with a pelagic trawl at the depth of the trace. This work was reported in a ‘letter’ to the journal Nature in 1952. In 1950 the RV "Platessa" was involved in comparative
Pseudorhombus arsius Pseudorhombus arsius Pseudorhombus arsius, the largetooth flounder, is a species of left-eyed flatfish, that is the dark side with the eyes on the adult fish is the left side of the fish's body, from the family Paralichthyidae. As "Rhombus polyspilos" it was named as the type species of the genus "Pseudorhombus". It is an Indo-Pacific species and is fished for by both recreational and commercial fisheries. "Pseudorhombus arsius" has an oval-shaped body which has a depth which is 1.8 to 2.3 times its standard length. The head has a slight notch in front of upper eye. The eyes are on