Xliv PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



The wonderful discoveries of Cuvier, the philosophy of Lyell, the 

 anatomical skill of Owen, all became tributaries to Buckland in the 

 formation of this work, and it would be vain to attempt here a per- 

 fect analysis of its rich stores of knowledge or a full exhibition of the 

 abihty of its author by applying them to the illustration of his sub- 

 ject ; but I may point out the interesting manner in which he de- 

 scribes, as he had partially done before, the beautiful discovery by 

 Miss Anning of the ink-bags of cephalopoda in the has, and the 

 able explanation of the manner in which the siphuncle of cham- 

 bered cephalopods performs the supposed function of elevating or 

 depressing the animal in its aqueous medium. The object of this 

 mechanism had been guessed at, but the actual modus operandi had 

 not been explained, when Dr. Buckland, basing his argument on the 

 anatomical description of Owen, v,ho had traced the siphuncle or pipe 

 of the recent Nautilus from the small initial cham.ber up to a sac, 

 near the heart of the animal, filled with a fluid, the coat of the sac 

 and the non-elastic membrane of the siphuncle being both impervious 

 to water. Dr. Buckland assumes that this pericardial fluid, by being 

 forced into the siphuncle, then in a collapsed state and empty, adds 

 to the weight of the shell and sinks the animal ; or being withdrawn 

 from the siphuncle, diminishes the weight of the shell, which then 

 acts as a float and brings the animal to the surface*. 



I here close my remarks on the labours of. Dr. Buckland, and I 

 now think it desirable to point out in the strongest light those high 

 qualities which he possessed in no ordinary degree, namely, candour 

 and freedom from prejudice. I have explained his views of diluvial 

 action, embraced as they had been with all the natural fervour of his 

 character ; and yet, when Agassiz made his appearance amongst us 

 as the propounder of a glacial theory, which was in his opinion to 

 explain the pheenomena of erratic matter of every description, no one 

 welcomed him with more ardour or more zealously set to work to 

 trace out the glaciers of Great Britain than Dr. Buckland : but I 

 must stop ; this leader amongst us has indeed passed away, but he 

 has left abundant records of the high position he so long oceupied 

 amongst geologists, and of the great value of his unremitting labour. 

 Dr. Buckland possessed great natural strength of body, which made 

 him equal to any amount of exertion, and Sowerby has recorded the 

 anecdote of his galloping offwith a huge ammonite over his shoulders, 

 his head passed through the opening occasioned by the loss of the 

 central volutions, when his companions dubbed him on the spot an 

 Ammon-Knight ; his invariable cheerfulness and humour threw life 



* Beautiful as this explanation is, it must be received with hesitation, so far 

 as respects the rise or fall of the animal, as it must be remembered that the fluid, 

 assumed to be incompressible, still remains, in either case, in the animal, and 

 therefore neither adds to nor diminishes its absolute weight. By changing its 

 position, it causes the shell to rise above or sink below the animal, but the actual 

 depression or elevation of the animal depends on the increase or diminution of 

 its specific gravity by the sudden retraction of the animal within the open ter- 

 minal chamber of the shell, or by its sudden expansion beyond it, when the peri- 

 cardial fluid enters the body and depresses it in position below the shell, which 

 then rises with it to the surface. 



