PLATE V. 

 Geiuis Tetragraptus, Salter. 



FIGS. 



1 a — e. — Tetragraptus quadribrachiafns (Hall). 



] a. Fairly preserved example from Outersicle. Skiddaw Slates. 



British Mviseum (Natural History), S. Kensington. 

 1 h. Specimen indifferently preserved. Haykin Gill. Skiddaw Slates. 



Woodwardian Museum. 

 1 c. Ibid. Randal Crag. Skiddaw Slates. Postletliwaite's Collection. 

 1 d. Small specimen, well preserved, showing details of thec^e. Barf. 



Skiddaw Slates. Woodwardian Museum. 

 1 e. Single stipe. Figured, Hopkinson, Quart. Journ. Geol. Soc, 



1875, pi. xxxiii, figs. 9 a, b. Whitesand Bay. Middle Arenig 



(Hicks). Woodwardian Museum. 

 2. — Tetragrajdus crncifer (Hall). 



Poorly preserved specimen, but showing disc. Barf. Skiddaw 



Slates. Postlethwaite's Collection. 



3 a, h.—Tetmgrapttts Headi (Hall). 



3 (I. Indifferently preserved specimen, showing large disc. Randal 

 Crag. Skiddaw Slates. Postlethwaite's Collection. 



3 h. Very large specimen, without disc. Randal Crag. Skiddaw 



Slates. Lapworth's Collection. 



4 a — c. — Tetragraptus Amii, Lapworth, MS. 



4 a. Specimen well preserved, ])ut showing three complete stipes only. 



White Horse, N.W. of Skiddaw, above Barkbath Dale. 



Skiddaw Slates. AYoodwardian Museum. 

 4 h. Typical form. On same slab as 4 a. 

 4 c. Specimen distorted by cleavage. Figured by Hopkinson as 



Tctragrapdus serra, Quart. Journ. Geol. Soc, 1875, pi. xxxiii, 



fio-. 10. Whitesand Bav. Woodwardian Museum. 



