88 



BRITISH FOSSIL CRUSTACEA. 



Banks's Cabinet). Base of Old Red Sandstone, Ludlow Railway Station (Museum of 

 Practical Geology). Cornstones of Hopton Gate (Cabinet of Mr. J. Harley). 



Fig. 20. — Thoracic plate, copied from an unpublished sketch by Mr. J. W. Salter, and referred by him to 

 Pterygotus problematics, Ag. Locality of specimen unknown. 



One of the most widely spread species ; it is probably this which occurs in the Upper 

 Llandovery Rock or " May Hill Sandstone" of the Obelisk, Eastnor Park. 



Several fragments, probably belonging to this species, have been obtained from the 

 Wenlock Shale and Limestone (together with other remains referable to Eurypterus 

 punctatus), from Dudley and Malvern, and are preserved in the British Museum, and in 

 the Cabinet of John Gray, Esq., of Hagley, and in those of Messrs. Henry Johnson, E. 

 Hollier, and C. Ketley, of Dudley. 



Species 9.— PTERYGOTUS ARCUATUS :— Salter. 1859. 



Ptekygotus arcuatus, Salter. Mem. Geol. Surv., 1859, Mon. I, p. 95, pi. xiii, figs. 



8, 12, 13, 15, and 16. 



This name is applied to a large and fine species, of which several fragments occur in 

 the Lower Ludlow Rock of Leintwardine, with the more common P. (now Eurypterus) 

 punctatus. It is clearly distinct from that species ; but, except for the total absence of any 

 minute interspersed plicse, the body-segments might be easily mistaken for those of 



