*266 



Another species, the representation of a mutilated fragment of which 

 is given Plate XVII. Fig. 16, is a very extraordinary fossil. In this ani- 

 mal, 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 pro- 

 tuberances are closely beset with small tubercular risings. These pro- 

 tuberances possess nearty 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 disposition 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 inferior 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 process itself, the impression only of its 

 lower surface being left, and which possesses somewhat of a bronzed ap- 

 pearance, 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 Shropshire 

 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 de- 

 scribed. Of the head, very little can be made out : it is evidently, how- 

 ever, much larger in proportion than that of any of the former species. 



