145 



stance belonging to corals, but that it was formed of a substance, 

 whose alcyonic texture is yet to be seen. This body, invested with 

 its highly-coloured cortical substance, as the figure shews, being dis- 

 posed in deeply indented folds, somewhat like the heraldic nebule, 

 must have possessed, in an eminent degree, the power of enlarging or 

 diminishing the cavity which it formed, by extending, and straighten- 

 ing, or contracting, and corrugating the line in which it was disposed. 

 As has been seen in two or three other instances, the original colour of 

 the animal, being here a reddish brown, has been preserved. 



But to return to the Maestricht fossil. With respect to its stellu- 

 lar columns, and connecting filaments, there can be no difficulty in 

 considering them as constituting a fossil whose form is the most sin- 

 gular, and whose history is the most difficult to make out, of any 

 which have come under our examination. Not only does it differ ma- 

 terially, from any known recent zoophyte ; but* even, from any fossil, 

 which, in my knowledge, has been discovered in any other part of 

 the world. 



In the fossil substance which comes next under our examination, 

 insuperable difficulties will, I believe, oppose its arrangement under 

 any existing genus. It is figured in Knorr's elegant work. (Suppl. 

 Tab. VI. Fig. 1). This fossil has been considered by many as an in- 

 crusted millepore ; by Mons. Guettard it has been supposed to be a 

 coralline ; and by Mr. Walch, who observes that it bears no marks, 

 either externally or internally, of a coralline, it is believed to be an al- 

 cyonium. After inspecting the specimen figured Plate XII. Fig. 13, 

 with the utmost care and attention, I was unable to concur with any or 

 the opinions which had been formed respecting this fossil. Upon exa- 

 mining the largest and most distinct branch with lenses of different 

 powers, I was obliged to consider the marks on its surface, as bear- 

 ing no analogy with those peculiar to the surface of a millepore. In- 

 stead of pores, a lens of considerable magnifying power, enabled me 

 to discover, that the surface was marked by minute tuberculated lines 



VOL. II. U 



