1855.] BANKS TILESTONES OF KINGTON. 101 



EXPLANATION OF PLATE II. 



Fig. 1. Pteraspis truncatus, Huxley and Salter. 



1 a. Cephalic buckler, or head, showing the upper surface ; natural size. 



I i. Cephalic buckler, or head, showing the upper surface ; enlarged one- 

 half, to show the striae. 



1 e. Cephalic buckler of another specimen (natural size) ; the greater 

 part of the surface has been destroyed ; the striae remaining in 

 parts, and elsewhere the granular layer visible. 



1 d. Profile of part of a head : the granular layer is seen, and in parts the 



striated dermal covering also. 



Fig. 2. Pteraspis BanJcsii, Huxley and Salter. 



2 a. Natural cast of the interior of a cephalic buckler ; natural size. 



2 b. Portion of the anterior part of a cephalic buckler ; natural size : the 

 upper striated layer has been worn away. 



2 e. Fragment of buckler, highly magnified ; showing the constituent layers. 



2 d. Eye-like marginal protuberance, — one of these is situated on each 

 side of the anterior projection of the buckler. 



Fig. 3. Portion of a head, similar in structure to the others, but imperfect ; 

 natural size. Only one specimen has been found. From the grey 

 layer. 



Fig. 4. Eurypterus pygmcBUs, Salter. 



4 a. The head and five of the body-rings (Mus. Banks). 



4 b. The head of another specimen (Mus. Geol. Survey). 



Figs. 5 & 6. Himantopterus BanJcsii, Salter (Mus. Banks and Geol. Survey). 



5 fl, 5 5, 5 c. Heads of difi^erent individuals. 

 5 ^, he. Body-rings of different individuals. 



6. Probably a caudal spine of an individual belonging to this species. 



