LETTER X. 



MYCETIT^E OF WOODWARD PO11PITAL AND TURBINATED COM- 

 POUND MADREPORITES RAMOSE MADREPORITES MILLEPO- 



RITES CELLEPORITES, &C FOSSIL CORALS OF UNKNOWN 



GENERA. 



THE bodies whose nature we shall next inquire into, have fre- 

 quently engaged the attention of oryctologists, in consequence, not 

 only of their being creatures of a former world, but of the great variety 

 of appearances which they yield, and the considerable differences 

 which exist between them and any of the recent coral bodies at pre- 

 sent known. 



This class of bodies does not appear to have been hitherto examined 

 with that attention which they seem to merit. Dr. Woodward, who 

 has investigated their structure more carefully than any one else, dis- 

 tinguishes them as mycetita coralloides, and divides them into mycetitas 

 conoides, sen calyciformes, and mycetitcz forma compressa, sen discoides. 

 But guided only by their conoidal or discoidal form, he blends the 

 simple madreporite, the porpital, and turbinated, each containing one 

 star, already examined, (Page 23,) with those of this class, which are 

 composed of several stars ; and which, not having been yet separated 

 from those other bodies of a somewhat similar form, but of a totally 

 different structure, I shall take the liberty to distinguish as porpital 

 and turbinated compound madreporites. 



The first of these (the porpital) is of a discoidal form; it has a 

 superior, slightly convex, stellated surface ; and an inferior surface, 

 which is generally concave, and finely marked by radiating striae and 



