49 



From the centre of each star forming the upper part of the cup, 

 proceeds another cup-formed coral, the lower part of which, as it 

 increases, covers the lamellated superior surface of the lower coral, 

 from which it has grown. Thus this coral proceeds in its growth, and 

 as each of the joints enlarges, the inferior surfaces of the superior ones 

 approximate the more to the edges of the inferior ones: and as this 

 same process is, at the same time, carrying on upon numerous laterally 

 contiguous stars, the size of the coral frequently becomes considerable, 

 being sometimes as large as a man's head. Specimens of this size are 

 frequently found on the shores of the isle of Gothland. 



This fossil is described and figured in CoralUa Baltica, Fig. XL 

 The medium thickness of each joint of which is there said to be about 

 that of the little finger, and the length about the width of the thumb. 

 A sketch from the above work, shewing the mode of growth of this 

 madrepore, is given Plate V. b. At a in the same plate is a sketch 

 shewing the mode of growth peculiar to m. ananas, represented at 

 Fig. 1. 



The madreporite, Plate VII. Fig. 11, is one which I was favoured 

 with by that assiduous inquirer into subjects of natural history, 

 William Cunnington, Esq. of Heytesbury, in Wiltshire, who obtained 

 it from Steeple Ashton. 



Its inferior side, which has the remains of its radical attachment, is 

 very finely marked by minute longitudinal and transverse striae, which, 

 by crossing each other, give it somewhat of a finely reticulated ap- 

 pearance. The superior surface is stellated, being covered by stars 

 closely set, and formed of raised undulating radii. The mode of in- 

 crease peculiar to this corallite is curious and interesting. It appears, 

 that when one area of its curious stellated fabric was completed, by the 

 labour of its polypean inhabitants, another colony laid the foundation 

 of another city on some part of the former surface ; and thus another and 

 another colony laboured, until several areas were formed. Then, as 

 the work proceeded, the nature of the structure became changed : the 



VOL. II. H 



