LOWER LIAS : FKOPINGHAM. 
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Ammonites capricornus. 
Henleyi. 
lataecosta. 
Loscombei. 
raricostatus. 
Taylori. 
Belemnites clavatus. 
paxillosus. 
Inoceramus ventricosus. 
Modiola scalprum. 
Pecten sequivalvis. 
lunularis. 
Pholadomya ambigua. 
Pinna folium. 
Pleuromya costata. 
Plica tula spinosa. 
Unicardium cardioides. 
Spiriferina. 
Waldheimia numismalis. 
Pentacrinus. 
Gryphaea cymbium. 
Hippopodium ponderosum. 
Lima pectinoides. 
This assemblage is suggestive of the zones of A. armatus, 
A. Jamesoni, and the lower part of that of A. capricornus. 
Above these clays comes a band of ironstone about 4 feet thick, 
named by the Rev. J. E. Cross the " Pecten-ironsione." This 
Pecten-bed contains the following fossils : 
Ammonites armatus. 
Henleyi. 
.. . striatus. 
Belemnites elongatus. 
Cardinia hybrida. 
Listeri. 
Cardita multicostata. 
Cypricardia intermedia. 
Gryphsea cymbium. 
gigantea. 
Lima antiquata. 
Hermann!. 
Modiola scalprum. 
Pecten sequivalvis. 
lunularis. 
Pleuromya costata. 
Tancredia ovata. 
Rhynchonella tetrahedra. 
variabilis. 
Terebratula punctata. 
This assemblage (with the exception of A. armatus) is essentially 
one characteristic of the higher stages of the Lower Lias ; the 
presence of forms like Cypricardia intermedia recalls brds at 
Chipping Norton, which belong in part to Lower and in part to 
Middle Lias. The Pecten-bed has been traced from near Winter- 
ingham to the neighbourhood of Kirton Lindsey, but not far 
southwards of that locality. 
Overlying the Pecten-bed there is a series of clays with 
ferruginous nodules and septaria, over 60 feet in thickness, which 
appear to contain Am. capricornus throughout. No specimens of 
A. margaritatus are known from this division, but it is directly 
overlaid by the Marlstone Rock, or upper part of the Middle Lias. 
These clays were exposed in the railway-cutting south of Santon 
Warren, where they yielded the following fossils : * 
Ammonites capricornus. Pecten aequalis. 
Belemnites paxillosus. 
Avicula inEequivalvis. 
Pholadomya ambigua. 
Plicatula spinosa. 
Near Cleatham Grange Hippopodium ponderosum, Belemnites 
tubularis, &c. have been found. 
In the absence of Ammonites margaritatus, and looking to the 
general character of the fauna of these beds, it is best to regard 
them as belonging to the zone of Ammonites capricornus. 
It is possible that further researches may show that Am. mar- 
garitatus occurs in the top beds of this clay-series : the zone being 
very much attenuated. The Pecten-bed was however taken as 
the base of the Middle Lias by Mr. Ussher, as it afforded a 
convenient boundary in mapping the district. 
* Ussher, Geol. N. Lincolnshire, p. 42. 
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