34 



hollowed out towards the centre. The rays composing the star, and 

 which converge from the edge towards the centre, are dentated, and 

 are of two orders; the larger being placed alternately with the smaller. 

 The representation, Plate IV. Fig. 6, yields a very correct idea of the 

 appearance presented by the disk of this fossil. 



Whilst examining the various specimens of fossil madrepores in my 

 possession, I was very much struck with the beautiful appearance of 

 the turbinated madreporite from Sweden, which is figured Plate IV. 

 Fig. 11 ; and particularly observed, that the rays had an appearance 

 totally different from those of any other which I had noticed. The 

 form of this madreporite places it indubitably among the turbinated 

 madrepores ; it gradually narrowing and terminating in a curved 

 pedicle. Innumerable striae, which are intersected by horizontal ridges 

 and depressions, most closely and neatly arranged, mark the whole of 

 its inferior surface. 



The disk derives a rich appearance from the perpendicular radiating 

 laminae which form the star, being arranged alternately in a larger and 

 smaller size, and being also closely beset with rounded annular pro- 

 tuberances : the whole of the superior part of the coral bearing an 

 exact resemblance to the disk of the porpital madrepore. Indeed, so 

 exactly does it resemble this fossil, that I feel no hesitation in con- 

 sidering them as being both of the same species ; and as differing from 

 each other only in their having undergone the lapidifying process at 

 different stages of their growth. Nor do I perceive in the porpital 

 madrepore, the least reason for doubting that it possessed a pedicle 

 of the same kind with the larger specimen ; but being proportionably 

 less, it must have been so much more liable to be removed. 



The celebrated Linnaeus has considered the absence of a pedicle in 

 this madrepore as one of its first specific characters. It is considered 

 and described, both by Buttner and by Bromell, as the head or 

 top of some small marine fungus: neither of them having discovered 

 any remains of a pedicle by which it could have been attached to 



. 



