CEPHALOPODA. 337 



water Treatise ; and, like it, differs from Mr. Miller's restoration, 

 only in the position of the ink-bag and in the extended state of the ter- 

 minal fins. With respect to these parts, ]M. Duval, from his dis- 

 covery of the united fractures of the spathose guard, objects, with 

 much acumen, that, if the fins of the Belemnite had been placed at 

 the side of the guard, they must have been rendered useless by its 

 fracture, and the creature, thus deprived of its power of swimming, 

 would soon have fallen a prey to its numerous enemies, and would 

 not have survived to exemplify the reparative powers of those ancient 

 Cephalopods. M.Duval, however, modestly concludes by confessing 

 that he should not have dared himself to figure from the known anal- 

 ogies, the animal to which the Belemnite ought to have belonged ; 

 for " I have not," he says, " a sufficiently exact knowledge of the 

 organic laws of the Cephalopoda." * It seemed vain to hope that 

 the soundness of the principles on which the classification of the 

 Belemnites with the dibranchiate Cephalopods had been definitely 

 proposed, should ever be vindicated by an example of parts appa- 

 rently so perishable as the mantle, the fleshy arms and fins of these 

 Mollusca. I have however the gratification to be enabled, by the 

 kind permission of the Marquis of Northampton, to place before 

 you a specimen of a Belemnite, in which not only the ink-bag 

 but the muscular mantle, the head, and its crown of arms, are 

 all preserved in connection with the Belemnitic shell. It appears 

 to have been the peculiar property of the matrix, in which this and 

 many similar valuable and instructive specimens were entombed, to 

 favour the conversion of the muscular tissue into adipocire, and its 

 subsequent preservation to the present time. Yet this matrix is a 

 member of the Oxford-clay-formation, belonging to the middle oolite 

 system ; older, therefore, than the Portland stone, the Wealden and 

 the Cretaceous group. The Cephalopod, in which we may now study 

 the microscopic character of the muscular fibre, must therefore have 

 existed at a period antecedent to the gradual deposition of these 

 enormous masses of the secondary strata, which themselves preceded 

 the formation of the entire tertiary series, and the overspreading 

 unstratified masses called diluvial. The attempt to conceive or cal- 

 culate the period of time which must have elapsed since the Belem- 

 nites were thus embalmed, baffles and awes the imagination. 



A second, less complete, but highly instructive, specimen of the 

 Belemnite, from the collection of Mr. Pratt, to whom I am indebted 

 for the first knowledge and inspection of the soft parts of these extinct 

 Cephalopods, exhibits the contour of the large sessile eyes, the funnel, 



* Loc. cit. p. 20. 



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