34: TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



left pleasant memories of the music and games at their social 

 evenings. Amongst other activities at Belfast he took a 

 prominent position at the Natural History and Philosophical 

 Society; the Belfast Naturalists' Field Club, and also the 

 Literary Society, at all of which he read papers. We hear that 

 he gloried in his beautiful garden and was a valued judge at 

 the local flower shows. 



It was during this period of teaching at Belfast that he 

 began to make his mark in the scientific world as a marine 

 biologist who studied animals both living and extinct, and 

 published his investigations on British Coelenterates and 

 Polyzoa and on fossil Cirripedes and Trilobites. In working 

 at Palaeontology he became interested in fossil Crinoids, and 

 so was led to the investigation of their only living representa- 

 tives in our seas — -the Rosy Feather Stars — a study which 

 we shall see led him step by step to the great climax of his 

 career, the leadership of the ''Challenger" Expedition. In 

 1862 Thomson completed his well-known memoir " On the 

 Embryogeny of Antedon rosaceus " (published in the 

 Philosophical Transactions of the Royal Society for 1865), 

 illustrated by a beautiful series of drawings representing 

 the development and structure of the " pentacrinoid " stages 

 in the life history of the young Antedon. 



It was at this time, also, that he became interested in 

 those questions concerning life in the great depths of the 

 ocean, the elucidation of which was to be his life-work and 

 make him famous. It will be remembered that Edward Forbes, 

 from his observations in the Mediterranean (an abnormal 

 sea in some respects), regarded depths of over 300 fathoms 

 as an azoic zone. It was the work of Wyville Thomson and 

 his colleagues on various successive dredging expeditions to 

 prove conclusively, what was beginning to be suspected by 

 Naturalists, that there is no azoic zone in the sea, but that 

 abundant life belonging to many groups of animals extends 



