THOMSON, SIR CHARLES WYVILLE Scottish naturalist, director of the scientific staff in the Challenger Expedition, was born at Bonsyde, Linlithgowshire, on March 5, 1830, and was educated at Edinburgh University. He held pro fessional appointments at Aberdeen and in Ireland, and finally (187o-79) was professor of natural history at Edinburgh. He died at Bonsyde on March io, 1882. He will be specially remembered as a student of the biological conditions of the depths of the sea. His interest in crinoids was stimulated by the results of the dredgings of Michael Sars (1805-1869) in the deep sea off the Norwegian coasts, and he succeeded, with Dr. W. B. Carpenter, in obtaining the loan of H.M.S. "Lightning" and "Porcupine," for successive deep-sea dredging expeditions in 1868 and 1869. These operations showed that animal life exists in abundance down to depths of 65o fathoms, that all invertebrate groups are rep resented (largely by Tertiary forms previously believed to be extinct), and, moreover, that deep-sea temperatures are by no means so constant as was supposed, but vary and indicate an oceanic circulation. The results of these expeditions
were described in The Depths of the Sea (1873). The govern ment realised the value of the work and provided H.M.S. "Chal lenger" for a circumnavigating expedition. Thomson sailed at the end of 1872 as director of the scientific staff, the cruise lasting three years and a half. (See CHALLENGER EXPEDITION.) On his return he received many academic honours, and was knighted. In 1877 he published two volumes (The Voyage of the Challenger in the Atlantic) of a preliminary account of the voyage.
See obituary notice in Proc. Soc. Edin. (1883) ; also Thomson and Murray, Reports of the Voyage of H.M.S. "Challenge?' (Edinburgh, 1885).