PROFESSOR OWEN ON THE BELEMNITE. 
83 
cannot doubt, but that, like the uncinated Calamaries of the present seas, the ancient 
Belemnites and their associates, the Celaenos, were, in their day, the most formidable 
and predaceous of Cephalopods. 
We admire the skill of the Egyptian embalmers, which has enabled Cuvier* to 
test the influence of time in transmuting specific forms, by a comparison of the Ibis 
of the present century with one that died 3000 years ago. The researches of the 
chemist may afford an insight into those properties of the soil, in which the above 
described valuable and instructive specimens of Cephalopoda were entombed, that 
favoured the apparent conversion of their muscular tissue into adipocire, and its 
subsequent preservation to the present day. I can only describe this conservative 
matrix as a peculiarly fine and compact, but fissile, laminated variety of the Oxford 
clay: a formation at the base of the great middle oolitic system, more ancient than 
the Portland stone, the Wealden and the entire Cretaceous group. The Cephalopods 
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 calculate the period of time which must have elapsed 
since the Belemnites were thus embalmed, baffles and awes the imagination. 
Description of the Plates. 
All the figures are of the same species of Belemnite (Bel. Owenii, Pratt), and of 
the natural size, except where otherwise indicated. 
The following letters indicate the same parts in each figure. 
a. The guard. 
b. The alveolus or socket of the guard for lodging, — 
c. The phragmocone ; the sheath ; 6, septum ; /, siphon. 
d. Muscular tunic of the mantle; q, fold of the sheath. 
e. The pallial fins. 
f. The infundibulum. 
g. The levatores infundibuli. 
h. Decussating muscular fibres of the head. 
i. The uncinated arms. 
k. The tentacula. 
l. The eyes (?). 
m. The lining or muscular tunic of the stomach. 
n. The ink-bag. 
* Discours Pr^liminaire sur les Revolutions du Globe, Ossemena Fossiles, tom. i. p. 141. 
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