244 GEOLOGY OF THE ISLE OF WIGHT. 



having a root-like base by which the original was 

 attached to the rock. This fossil was first figured 

 and described by Mr. Webster, under the name of 

 tulip alcyonium. The bulbs and steins are often 

 disposed in relief on blocks that have been wea- 

 thered, or washed by the sea ; for the fossils, 

 being harder than the surrounding stone, more 

 effectually resist abrasion, and large surfaces of 

 firestone are therefore covered with their remains, 

 which, being whiter than the rock, are very con- 

 spicuous. 



Fossil Cycadeous plant. — But the fossiliferous 

 marl (as Captain Ibbetson designates the bed most 

 prolific in organic remains) has lately been found to 

 contain relics of a higher order than any previously 

 known to occur in the cretaceous strata of the Isle 

 of Wight. In the collection deposited in the Poly- 

 technic Institution, there is a specimen from the 

 marl near Ventnor, that several years ago attracted 

 my attention, but which I was unable to obtain an 

 opportunity of examining till a few weeks since, 

 when Captain Ibbetson, with great liberality, per- 

 mitted me to inspect and figure it for this work. 

 It proved to be, as I had conjectured, the summit 

 of a stem, surrounded by the petioles, or leaf 

 stalks, the leaves themselves having either been 

 shed or decayed, of the Clathraria Lyettii, a 



