130 



and thence northerly about five miles to King's Langley, in Hertford- 

 shire, making a tract of road of upwards of thirty miles, I frequently 

 saw, in the road, flints of the same description. But at Watford, five 

 miles southwardly of King's Langley, and three miles east of Rickmans- 

 worth, very few of these flints were to be seen : a greyish flint, with a 

 brownish coat, not possessing any organic remains, appearing there to 

 be most prevalent. Aided by the specimens I procured in this route, 

 I was happy on being able to confirm the observations which had 

 been made by Mr. Townsend. 



On immersing these flints in water, it may be seen, even without a 

 glass, that the original animal body was composed of an internal, and 

 of an external or cortical part. In the internal part, in consequence 

 of its great degree of transparency, the vesicular or alcyonic struc- 

 ture is very plainly discoverable. In the centre of this part, in some 

 specimens, a ramifying opaque white tube is observable, and at that 

 part which appears to have been the line of union between the in- 

 ternal and the cortical part, fibres or tubules are seen closely placed 

 by each other, appearing to pass, in a converging direction, from 

 the opaque cortical part, towards the centre of the transparent inter- 

 nal substance. Most of these different circumstances are illustrated 

 by the representation of one of these flints from Wy combe Heath, 

 Plate XI. Fig. 4. 



Every circumstance which can be ascertained, respecting the ani- 

 mal substances thus inclosed, conspires to confirm the opinion, that 

 they were a species of alcyonium, invested with a cartilaginous or co- 

 riaceous covering. Very little to be relied on with respect to the 

 forms which these bodies originally possessed, can be inferred from the 

 different rude sections which are obtained by the fracture of these 

 flints, in different directions. From the figure of the alcyonium 

 which is observable in the flint from Wycombe Heath in Plate XL and 

 which, in a less perfect form, is frequently seen in the fracture of dif- 



