27*2 



of each of these, are two round tubercles. Adjoining to 

 this part commences a series of triarcuated, imbricating, 

 transverse slips, so disposed that the three bows of these 

 connected slips form three longitudinal transversely divided 

 lobes, gradually diminishing to the lower termination. In 

 some specimens the fossil is almost globular, showing that 

 the animal possessed the power of coiling itself occasionally 

 in this form. No elongated caudal termination is seen in 

 this species ; nor in the published representations of any of 

 the preserved remains of this animal have the traces of any 

 organs of progressive motion been given ; still it may be 

 conjectured that this animal was furnished with articulated 

 and unguiculated feet.* This fossil has been found in the 

 neighbourhood of Dudley nearly three inches in length. 



Another species is found in the schistose strata of 

 Llandilo, in Carmarthenshire, erroneously stated in Organic 

 Remains, to be Lanelly : for this correction, and much valu- 

 able information, I am under obligations to the Rev. Mr. 

 Hallifax. In these the outline of the animal approaches 

 rather to that of a long ellipses than to an ovate form : the 

 lateral lobular divisions of the dorsal plates or slips are 

 nearly three times as wide as those of the central part. 

 The crustaceous coverings are, in these species, generally 

 removed, leaving in some parts, however, a very accurate 

 impression of the inner surface, with regularly disposed 

 longitudinal minute rugae, appearing as if they had been 

 formed by the subjacent soft cuticle. — Organic Remains, 

 Vol. iii. PI. xvii. fig. 13. 



* I have seen the sketch (on the fidelity of which I can depend) 

 of a fossil animal of this kind, corresponding, in its feet, with the 

 above description ; and have also seen a specimen of the animal at 

 Clun, in Shropshire, in which I believe the points of the feet ap- 

 peared from beneath the superior covering ; but, on endeavouring 

 to detach the piece of rock in which it. was embedded, and though 

 working with the utmost care, the specimen was entirely shivered. 



