﻿PLATE XXI. 



DEVONIAN AND SILURIAN CRUSTACEA. 



Order — Merostomata. 



Sub- Order — Eurypterida. 

 Fig. 



1. Stylonurus Powriei, H. Woodw., nat. size. 



Old Red Sandstone; Turin Hill Range, near Pitscandly, Forfarshire. (P. 122.) 

 From the Collection of James Powrie, Esq., F.G.S., Reswallie. 



2. Stylonurus Powriei ? two detached swimming feet of large size, probably belonging 



to this species. (P. 123.) 



Upper Silurian ; Lesmahagow, Lanarkshire. 



From the Collection of James Powrie, Esq., F.G.S. 



3. Stylonurus megalops, Salter, sp. Head-shield, nat. size. (P. 1.24.) 



3 a. „ „ part of the head magnified, showing the granular surface. 



From the Collection of Robert Lightbody, Esq., F.G.S., Ludlow. 



4. Stylonurus Symondsii, Salter, sp. (P. 124.) 



Upper Beds of the Comstones, Old Red Sandstone ; Rowlestone, Brecknockshire. 

 Head-shield, nat. size. 



From the Museum of Practical Geology, Jermyn Street. 



5. Stylonurus ensiformis, H. Woodw. Tail-spine, nat. size. (P. 126.) 



Old Red Sandstone ; Turin Hill Quarries, Forfarshire. 



From the Collection of James Powrie, Esq., F.G.S. 



