284 Antediluvian Zoology and Botany. 
shells, but their forms are too singular to be passed without 
separate notice. The structure of these animals has been 
subjected to the examination of Messrs. Parkinson, T. Allan, 
and Miller, and, lastly, of M. de Blainville, in his memoir on 
Cephalopodous Mollisca. 
Illustrations of Mr. Miller’s article on Belemnites, in the Transactions of 
the Geological Society, New Series, vol. ii. pl. 7, 8, and 9. 
se | 
a, Section of a Belemnite, showing 
the chambers filled with spar. 
b, Section showing the siphtnculus 
within the conic-chambered shell. 
c, Belemnites elongatus, of the lias, 
exhibiting the chambered cone 
partly enclosed by the laminated 
guard ; its inhabitant being a Sepia. 
d, Belemnites minimus, of the gault. 
e, Mr. Miller’s new genus <Actind- 
camax, without a chambered cone. 
These bodies are determined to be concamerated shells, 
intermediate between the bony Sépia and the shelly Nautilus. 
They are found in almost all the formations from the lias to 
the chalk, but not in the slate formation, or in mountain lime- 
stone; neither have they been found in the beds above the 
chalk. In the first case (the slate and mountain limestone), 
M. de Blainville conceives their places were supplied by the 
