225 



one eighth of an inch in diameter, from which they taper, in regular gra- 

 dation, to a point; the tentacula consist of many articulations. The 

 main stem seen in this mass is of a circular form, somewhat hollow 

 within, having the edges rounded off, and a small hole in the centre. 

 There were several fragments of branched madrepores, and striated 

 shells of the anornia genus, also imbedded in the stone/' 



From Dudley, in Worcestershire. 



LETTER XXII. 



THE TORTOISE ENCRINITE....THE STRAIT ENCRINITE.. ..THE BOTTLE 



ENCRJNITE....THE CLOVE ENCRINITE KENTUCKY ASTERIAL 



FOSSIL.. ..UNCOMMON ENCRINAL VERTEBRAS.. ..FOSSIL, APPARENT- 

 LY AN OVAL ENCRINITE. 



THE first mention which I find made of any part of the extraor- 

 dinary fossil, which, from the disposition of the plates of which it 

 is formed, may be termed the TORTOISE ENCRINITE, and whose 

 nature I shall now attempt to investigate, is in Mr. Lister's paper on 

 the Radices Entrochorum *, already noticed. He there gives an en- 

 graving of one of the plates of this animal, which he describes only 

 as, " a pentagonous plate embossed with angles/' 



One of these plates, from the chalk-pits in Kent, is exhibited, Plate 

 XIII. Fig. 30, adhering to its chalky matrix. A considerable degree 

 of variety is observable in the markings on these scales ; those which 

 are seen on the scale here figured, showing, from their extreme irregu- 



* Philosophical Transactions, No. 100, February 1614. 

 VOL.11. GG 



