PLATE VII. 



FIG. 1. An elongated alcyonite from Touraine. In the superior part is seen the alcyonic 

 texture; the calcareous matter having been removed by an acid, and the 

 reticular silicified texture left. 



2. A longitudinal section of the perpital madreporite ; the inferior surface of which 



is represented, Fig. 4; and its superior, Fig. 5. 



3. The under surface of an interesting compound madreporite of the porpital species 



from Dudley. An outline of part of its superior surface is represented, Fig. 7. 



4. The inferior surface of a porpital compound madreporite. In the centre is the 



pedicle, which is surrounded by successive risings and depressions, concentri- 

 cally arranged. 



5. The superior surface of the porpital compound madreporite, the inferior surface 



of which is shewn at Fig. 4. Here crenulated openings are seen, surrounded 

 by similar openings of a smaller size. 



6. A ramose alcyonite, from Berkshire, bearing some resemblance of Alcyonium 



Digitatum. 



7. The magnified appearance of part of the superior surface of the madreporite, 



represented Fig. 3, and which may be assumed as representing also the general 

 alcyonic texture. 



8. A magnified representation of the cruciform spines existing in the surface of the 



following fossil. 



9. An alcyonite, somewhat resembling in its form Alcyonium Cydonium of Linnaeus. 



10. A compound madreporite of the turbinated species. Its general character re- 



sembles that of the fossils shewn at Fig. 2, 3, 4, and 5, excepting that by a 

 protraction of the labours of the polypes several areae have been formed, each 

 extending beyond the last formed. 



11. A stellated madreporite from Steeple Ashton. On its superior part is a sketch, 



shewing the manner and form in which madrepores of this species increased. 



12. A ramose alcyonite, from Berkshire. 



