1872.] BLAKE YORKSHIRE INFRALIAS. 147 



4. CrTHERE Terqtjemiaxa, sp. nov. 



Carapace narrow-obloug, incurved on the back by the projection 

 of the anterior hinge, and pinched in between that hinge and the 

 muscle-spot ; rounded at the ends, with broad delicate margins, that 

 of the front divided into about eight neat fossets. Surface sculp- 

 tured with a coarse, irregularly hexagonal network, about eight 

 meshes to the transverse width of the valve. 



Length -^ inch. Three specimens. 



This form reminds us of the Tertiarj' Cy there canaliculata (Reuss) 

 and its varieties ; but its compression is stronger and more central, 

 and its reticulation has far less tendency to run into ridges by the 

 hypertrophy of the meshes. 



This species is dedicated to M. 0. Terquem, the veteran explorer 

 of the Lias of Metz and its neighbourhood. 



Discussioisr. 



Prof. DuNCAiSr remarked that English geologists had been back- 

 ward in receiving the term Infralias, which he had suggested with 

 respect to the Sutton Down beds some years ago, and the propriety 

 of which was shown by the term having been applied to the same 

 beds by French geologists at a still earlier period. As to the White 

 Lias, he regarded it as a mere local deposit, not to be found out of 

 England. He traced the existence of the Infralias from Luxem- 

 bourg through France into South "Wales, where Corals were abun- 

 dant. In Yorkshire, though one fine Coral had been found, the 

 Ammonites seemed to point to a difference in condition. 



Mr. Hughes remarked that the lithological character of the beds, 

 as described by the author, did not agree with that of the Infralias 

 in the S.W. of England or the N. of Italy, and that the palasontological 

 evidence which had been laid before the Society did not confirm the 

 view that they were Infralias. Also, by reference to the author's 

 section, Mr. Hughes pointed out that below what he described as 

 Infralias he drew other beds which were not Trias, the author having 

 explained that some beds which had been called Trias were only 

 stained beds of Liassic age. 



The Rev. J. F. Blake, in reply, acknowledged the dififerencce 

 between the Yorkshire section and those of the neighbourhood of 

 Bath, but insisted on the similarity of the fossils. 



Februaky 7, 1872. 



"W. G. Thorpe, Esq., of Gloucester House, LarkhaU Rise, S.W., 

 and Barton's House, Ipplepen, Newton Abbot, and James Plaat, 

 Esq., of 40 West Terrace, West Street, Leicester, were elected 

 Fellows of the Society. 



The following communications were read : — 



