Salpa whose ship’s bell hangs above, was the sea-going facility of the Marine Biological Association from 1921 to 1939. She was an 88ft long, coal burning, ex-Admiralty steam drifter/trawler, built for minesweeping in World War I. Originally named Nadir, she entered service in July 1921, and in the next year was fitted with a small deck laboratory but always maintained a reputation for being an uncomfortable vessel for scientific work. During her eighteen years as a research vessel, she maintained the regular quarterly line of stations from Plymouth to Ushant as well as the monthly sampling at E1 and, from 1924, the weekly sampling at the Eddystone. After 1935 this activity was restricted to the E1 and Eddystone stations, but her trawling activities were essential for the supply of specimens for experimental work. At the outbreak of World War II, Salpa was decommissioned and handed back to the Navy. In 1946 she was deemed unsuitable for the MBA research programme and was replaced by a larger (90ft) ex-Admiralty chartered Motor Fishing Vessel, Sabella.