44 
spoken of, not only the articulating- termination, but so much of the 
colour and surface preserved, as determines its echinital origin ; and, 
on the other hand, we have the concamerated shell, or the alveola, 
which contained it, evincing the fossil to be a belemnite. But much 
more frequently we meet with fossils, in which, from having been 
broken, rubbed down, or otherwise injured, these parts are entirely 
removed, and their figure so altered, that it is no longer possible to de- 
termine in which class of fossils they are to be placed. The discovery 
of this specimen induced me to examine, with more care, those fossils 
in my possession, which had been hitherto regarded as belemnites ; and 
I was much pleased at soon perceiving that many, which I should be- 
fore, without hesitation, have termed belemnites, were in all proba- 
bility spines of echini. In three specimens, this origin was indubitable. 
Plate IV. Fig. 4, shows a hard and heavy spathose specimen ; which 
although, from its form, I had often suspected to be a fossil sudes, I 
never could before assert it, in contradiction to the opposite opinion 
of many very excellent fossilists. Its triquetral form, extending through 
three fourths of its length, and insensibly gliding into the rounded 
conical termination, with something more than a fancied resemblance 
in colour, determined it, in my opinion, to have been originally an 
echinital spine, although the further proof of its articulating termina- 
tion is, by accident, destroyed. Plate IV. Fig. 19, represents a small 
specimen, in chalk, which appears to be a fossil spine of the same 
species with the preceding, but more rounded and fusiform : a small 
annular mark, at one end, shows, indisputably, its point of articulation. 
The spine, Plate IV. Fig. 14, hitherto supposed to be a belemnite, 
is of a species, not, I believe, described. The inferior extremity, though 
somewhat crushed, still yields marks of its having there had its articula- 
ting surface. It is rendered very different from any belemnite or echini- 
tal spine which I have ever seen, from its surface being pierced with nu- 
merous small, but distinct, and somewhat regularly disposed, foramina. 
Of the class Spathula, in which are comprised small flatfish spines. 
