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XVL The Fig Pentacrinite, of Gloucestershire, described in 
the Philosophical Transactions ; see Letter XXV. 
XVII. The Pentacrinite, of Yorkshire. 
To these I shall add the following fossils, which have been 
described by other authors, but whose rarity has hitherto 
prevented their nature from being duly investigated. 
XVIII. The Encrinites with four rays. This fossil is spoken of by 
Mons. Guettard, in the Memoirs of the Royal Academy of 
Sciences, for the year 1755.* He remarks that in this 
species of encrinite each of the principal rays is divided into 
two, which are again divided into two others, from which 
proceed a considerable number of small branches. The 
opinion of Mr. W alch, that this species might, perhaps, be 
referable to the pentacrinites, derives support from the 
existence of quadrilateral asterise, which would, of course, 
have belonged to a pentacrinite possessing four arms. 
XIX. The Encrinite with five or six rays. Such a fossil is described 
by M. Harenberg, in his treatise De Lilio Lapideo ; but it 
does not appear to have been seen by any other author. 
XX. The Encrinite with eight rays and a square base. This species 
is mentioned by M. Schulz, in his description of the petrified 
Stella marina. No other author appears to have described 
this fossil. 
XXL The Encrinite with twelve rays and a hexagonal base. This 
encrinite is figured and described by Rosinus, in Plate I. 
and page 34, of his excellent treatise de Lithozois. Rosinus 
describes the trochitge of this species as being characterized 
by concave articulating surfaces, bearing the figure of a 
pentapetalous flower, with a similar but much smaller 
floweret in the centre. 
* Recueil de Monumens des Catastrophes, &c. Tom. II. Sect, II. P. 89. 
