41 
orum, or pallisadoes, are composedof a porous substance, in consequence 
of which they do not sink in water as those of every other genus do. 
Among the numerous riddles which the admirers of fossils have to 
solve, there has been hardly any one more involved in puzzle than the 
01 iginal nature of the belemnite. A considerable progress had, how- 
evei , been made in removingthe mystery, when fresh difficulties started, 
in consequence of the peculiar appearances discovered in some fossils, 
which were sent to Klein by his friend Fischer, from Studtgard. 
These bodies, although of a dark colour and striated from the centre 
to the circumference, and generally considered to be belemnites, were, 
m the opinion of Klein, the spines of echini. Descriptions Tubul. 
farm. p. viii. To this opinion he was led by their figure, their seem- 
ing spathose substance, and by their striae concentering in a line passing 
longitudinally through the centre of the body, in which no trace of a 
canal was observable. Led by the examination of these bodies, which 
bore a resemblance so strong both to belemnites and to the spines of 
echini, he formed these, as it will appear, just conclusions -.—That all 
fossils, resembling belemnites in their substance and figure, are not to 
be referred to belemnites ; that all belemnites cannot be considered as 
spines of echini ; and that the substances naturally constituting the 
belemnite and the aculeated, if not all the spines of the echinus, were 
such as to be capable of undergoing the same kind of change. The 
fossil figured by Lhwydd, Lithoph. No. IJ02, Tab. xxi. as Belemnites 
minor cinereus art pistil lam referens; the shelled belemnite of Grew 
cn dies of Gi esham College, PI. 20 ; Belemnites su/catus niger major 
of Lang, us, Hist. Lap. Helv. Tab. xxx™. Fig. 3 ; Utrinque perquam 
acummatus of Ba,er Oryet. Noric. Tab. ,. Fig. 7 ; and others similar 
he conceives, should be considered as spines of echini, and similar to 
those which he received from Studtgard : but those fossils which pos- 
sess the conical cavity, the canalicula, and the alveola, he thinks must 
still remain among the belemnites, Descript. Tub. Marin, p o’ & c 
How far he was led in his suspicions, respecting these bodies, may 
ferred from the following remarks 1 Neque diffitebimur, pro- 
VOL. in. ^ 
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