126 REV. J. E. CROSS ON THE GEOLOGY OF N.W. LINCOLN SHIRE 



Cardium cognatum ?, Phill. 

 Lima rigidula, Phill. 



duplicata, Sow. 



Pecten lens, Sow. 



- rigidus, Sow. 



articulatus, Schl. 



insequicostatus, Phill. 



hemicostatus, Laube. 



subfibrosus, If Orb. 



Perna obliqua, Walton. 

 G-ervillia acuta, Sow. 



ovata. 



Avicula echinata, Sow. 

 Terebratula lagenalis, Schl. 



obovata, Sow. 



Bhynchonella concinna (dwarf). 



Serpula. 



Echinus. 



Appendix. By R. Etherilge, Esq., E.R.S., E.G.S. 



Mr. Cross's long- continued investigation into the geological struc- 

 ture and palseontological features of the Lias and Oolite of the N.W. 

 of Lincolnshire has resulted in obtaining and adding many new 

 species to the fauna of the Lower Lias, and some to that of the Inferior 

 Oolite. We now purpose figuring and describing 6 species — 3 from 

 the ironstone beds of the Lower Lias of Scunthorpe, and 3 from the 

 Inferior Oolite of Santon, or the Santon Oolite of the author. Eorms 

 of Ammonites new to Britain, but occurring in the same horizon in 

 Erance, have been discovered and catalogued in Mr. Cross's paper, 

 thus tending to show and correlate through this family of Cepha- 

 lopoda the close affinity of the Lias of France with that of England 

 through forms or species long looked for. To the species now 

 figured Mr. Cross had already given MS. names, which I retain, 

 but he did not describe them. An extremely rich fauna occurs in 

 this Lower-Lias iron-ore-bearing series of Scunthorpe. No less than 

 37 species have been found by Mr. Cross, and those chiefly, if not 

 entirely, from the zone of Ammonites semicostatus, Y. .& B., or 

 A. geometricus of Oppel, characterized also by the presence of 

 Cardinia gigantea, C. concinna, and C. copides. The extensive 

 workings carried on through the mining for and extraction of the 

 iron-ore at Scunthorpe has necessarily opened out a great area, 

 which has not been lost upon the author of this able paper, to 

 which I have added the following 'notes. 



The forms to be noticed are 1 species of Hippopodium, 2 of Tan- 

 credia from the Lower Lias, 2 species of the genus Cucullcea, and 

 1 Astarte. 



Tancredia, Lycett, 1850. 

 {Hettangia, Terquem, 1852.) 



The genus Tancredia was established by Dr. J. Lycett in 1850, 

 to receive a peculiar group of shells occurring in the Inferior and 

 Great Oolite of this country, T. donaciformis being the type. 

 Terquem and Buvignier have determined 12 species from the Lias 

 of Erance, none of which appear to be the forms here figured. The 

 species of this genus had but a limited range in time ; hence they 

 are important to the stratigraphical geologist. Hitherto, of the 20 

 species known in Britain, only three have occurred in our Lower 

 Lias, viz. T. ovata, T. securiformis, and T. tenera. These donaci- 

 form shells are all destitute of any ornamentation. 



