F03III. ALCYONIA. 



39 



He first was disposed to consider them as being similar to 

 the spongia elegans of Clusius, or the spongia dura of 

 Sloane, but this opinion he found reason to relinquish, and 

 was then induced to believe that they bore a nearer resem- 

 blance, in their general characters, to some species of ma- 

 drepores than to any of the sponges. In several of these 

 fossils he discovered an outer layer, which appeared to differ 

 from the general substance of the fossil ; and his opinion, 

 he thought, derived support from this circumstance, for, 

 on examining the interior lamina of these fossils, he con- 

 ceived that it much resembled the hard smooth part which 

 forms the corresponding parts in madrepores, &c. Madre- 

 pores and corals, he observes, are covered by a substance 

 which has been distinguished as their cortical part, and im- 

 mediately beneath this, there is a smooth substance of very 

 close and compact texture, in which there are no strise nor 

 traces of any fibres. AVith this latter substance, he thinks, 

 the external layer of these fossils exactly agrees: and he is 

 confirmed in the supposition that it originally belonged to 

 them, and was not derived from the matrix in which they 

 lay, by observing that, in one specimen, several little flat 

 shells of oysters were adhering to this surface. 



Nothing, he thinks, in the fossil kingdom approaches so Single starred 

 near to these fossils, as the single-starred corals of the cora J s of the 

 ^Baltic, described by Fougt. The only difference, M. 

 Guettard remarks, is that the corals described by Fougt 

 have ftriee which extend from the centre of the coral to the 

 edge, in such a manner as to form a star. This difference 

 is however sufficient to remove all idea of similarity between 

 the two bodies ; since, as we have already seen, the star 

 constitutes the genus Madrepora, to which those corals be- 

 long, whilst in the fossil bodies now under consideration, 

 there exist none of the characters which mark any of the 

 species of zoophytes, which we have hitherto examined. 



Many of these fossil bodies, it will be seen, differ so M any f ossi j s 

 much from any known recent zoophyte, that were it not apparently of* 

 that vaft numbers of these muft be concealed from us, in nwi , 8e " 

 the numerous recesses of the ocean, they would be con- 

 cluded to possess not the leaft resemblance with any animal 

 substance now exifting; indeed, so considerable is tnat 



difference, 



