ANIMALS. 135 



This species closely resembles the Devonian Atrypa ungidcida of J. de C. Sowerby, 

 as figured by Professor Phillips, in his 'Palseozoic Fossils of Cornwall' (pi. xxxviii, 

 fig. 119). None of my specimens exceed three sixteenths of an inch in width. 



Only a few specimens of Martinia Clannyana have occurred to me in one locality — 

 Ryhope Field-House Farm — in the Shell-limestone. 



Martinia Winchiana/ King. Plate X, figs. 14, 15, 16, 17. 



Martinia Winchiana, King. Catalogue, p. 8, 1848. 



Diagnosis. — Marginal outline nearly circular. Half an inch in diameter. Hinge 

 three quarters of the width of the valves. Large valve moderately convex : umhone 

 elevated, and slightly incurved : fissure open, triangular : dental plates rudimentary. 

 Small valve slightly convex : socket-plates large, and slightly divaricating. 



" This, which is a small species, resembles Martinia Clannyana in form, but both 

 valves are crowded with short, hair-like, declined, radiating spines."^ 



I have transcribed the above from my ' Catalogue,' but without vouching for the 

 concluding statement. I have only seen casts and impressions of this species, and in 

 all the latter there are numerous radiating, fibre-like markings, which I formerly 

 considered to be the remains of spines ; and it was in accordance with this view 

 that the restoration of the shell, represented in Plate X, fig. 17, has been given. A 

 recent examination of these impressions leaves the question an open one in my 

 mind ; though I still lean to my original view, qualified, however, with the supposition, 

 that the fibre-like markings may be the remains of a coarse fibrous tissue forming 

 the substance of the valves, similar to that already noticed occurring in Camaro- 

 phorias. 



The St. Kassian fossil represented in Count Miinster's ' Beitrage,' and identified 

 with Spirifer rostratus, appears to have a close resemblance to the present species. 



Martinia Winchiana is of very rare occurrence. I have only collected a few 

 specimens in one locality (Whitley); where they occurred in the lowest beds. 



Following the various genera of Spiriferida according to order of affinity, the one 

 requiring notice in the next place is a genus instituted by the author of the ' Synopsis 

 of the Characters of the Carboniferous Fossils of Ireland.' 



1 Named after Mr. Nathaniel J. Winch, the author of 'Observations on the Geology of Northumberland 

 and Durham,' in the 'Transactions of the London Geological Society,' 1st seues, vol. iv ; and some other 

 valuable papers illustrating the geology of the north of England. 



2 King, Catalogue, p. 8. 



