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animal, the lobular divisions seem to have very nearly corresponded 
with those of the Dudley species. But the structure of the head part 
of the animal differs exceedingly from every other species. In this 
fossil, instead of the appearance of the distinct parts of a face, there 
are three large round protuberances, the middle being the largest ; 
and all these protuberances are closely beset with small tubercular 
risings. These protuberances possess nearly the whole space of the 
head, the eyes being placed in the centre of each of the lateral risings. 
The matrix of this is a white fine limestone, but I am not able to say 
where it was obtained. 
The fourth species, which is much more rare than any of the former, 
is almost always found imbedded in fuller’s earth. The lower half of 
one of these is represented Plate XVII. Fig. 17- The form of the 
head I am unacquainted with. The structure of the back, and dispo- 
sition of its plates, appear to agree with that of Llanelly ; the central 
division of the plates terminating, like that of the Llanelly species, 
within a marginal line, which surrounds the divisions. From the in- 
ferior part of this line proceeds a long and narrow caudal process, 
which tapers as it descends, and appears to have been formed of a 
single plate or substance. These specimens seldom possess the pro- 
cess itself, the impression only of its lower surface being left, and 
wdiich possesses somewhat of a bronzed appearance, probably from 
some stain which the fullers’ earth has derived from the animal 
matter. 
Plate XVII. Fig. 18, represents another species as imbedded in a 
nodule of iron-stone from the neighbourhood of Bewdley, in Shrop- 
shire — a spot exceedingly rich in fossil vegetable remains, as I may 
infer from the valuable collection with which I was favoured by Thomas 
Botfield, Esq. of Hopton Court, near Bewdley. The species of this 
animal, which is here preserved, differs essentially from any of those 
above described. Of the head, very little can be made out : it is 
evidently, however, much larger in proportion than that of any of the 
