REV. J. E. CROSS ON THE GEOLOGY OE N.W. LINCOLNSHIRE. 119 



figured in his ' Middle Lias of the South-west of England.' If my 

 species is new, I propose to assign to it the designation "ferri." 



Another new shell (new, at least, in this country, and very common 

 in this bed) is a small Tancredia. It does not even seem exactly to 

 resemble any of the foreign Liassic species ; and I would give it the 

 name of "ferrea." 



But the prevailing fossils of the bed are the Cardinice. These 

 occur in countless multitudes, beautifully preserved, many of them 

 transparent, being filled with calcite, and of five or six different 

 species, among which the G. (Thalassites) gigantea of Quenstedt is 

 magnificently conspicuous ; the others are allied to C. crassissima 

 (Sowerby), cojoides (Ryckh.), regularis (Terquem), elliptica (Agass.) 

 or Morrisi (Terquem). I do not venture to name them till they 

 have undergone a further investigation. 



I think it is manifest, from this description of its fauna, that 

 this remarkable ironstone lies low down in the Lower Lias — say, on 

 the border-line between Quenstedt's « and [3; and I insist upon 

 this, and would call special attention to it, because it has been 

 hastily assumed, by those who are commercially engaged with it, 

 that it is of similar age with the marlstone-iron series of Cleveland. 

 This is quite impossible ; and if I am right, then, I take it, we 

 have here a development almost unique in this country ; for I doubt 

 whether any iron-ore so low down in the series is found in workable 

 quantity anywhere else (unless, indeed, it be a continuation of the 

 same bed that is worked at Caythorpe, near Grantham, a more recent 

 discovery, which has followed upon this one here). 



As regards its quantity and quality, it is some 27 feet in thick- 

 ness, and crops out upon the surface, covering the whole wide plain 

 of the village of Scunthorpe, so that no mining is at present re- 

 quired. It commences below with a hard limestone band, in which, 

 and in somewhat similar bands above, most of the fossils lie ; these 

 are intercalated with softer bands of a darker brown colour and 

 rubbly texture, intermingled with a brown dust. As it differs 

 from the well-known ore of Cleveland in its palseontological con- 

 tents, so it also differs from it mineralogically. The stone of 

 Cleveland is rich in silica, and requires a flux of limestone in the 

 furnace. This ingredient (silica) is almost wanting in the Scun- 

 thorpe stone ; and lime is superabundant. When first this ore was 

 worked, this excess of lime was not understood, and many hundred 

 tons of Oolite-limestone were brought, at considerable expense, from 

 neighbouring parishes, only to make bad worse. Most happily, with 

 the discovery of the real want came the discovery of the means of 

 supplying it ; a good iron-ore highly charged with silica has turned 

 up close to the city of Lincoln ; and this is now mixed with the mass 

 in the proportion of about J of the whole. 



The yield of metal is about 1 ton to 3^ of ore ; say, 27 or 28 per 

 cent. 



This important bed has now brought us to the foot of the 

 second or middle escarpment of the section fig. 2. I proceed to 

 ascend this second hill and to pass on eastwards. 



