208 J. E. BLAKE ON THE KIMMEEIDGE CLAY OP ENGLAND. 



At Holton-Moor Station, as before mentioned, a brickyard in this 

 region occurs with similar fossils, as far as examined — that is, those 

 that are most common at Market Basen, with the addition of Phola- 

 domya ventricosa (Sow.). More to the south two important pits in 

 this region are seen on the Wragby and Horncastle road, called the 

 Baumber and Langton pits. The latter, from its stratigraphical posi- 

 tion, must be lower in the series than the former ; yet its character- 

 istic univalve is Rostellaria mosensis, showing how little reliance can 

 be placed on that shell as indicating a zone. Neither of these is 

 so rich as that at Market Rasen ; and they have, besides, been less 

 worked. 



At Baumber two rows of doggers are visible — one smaller set 

 near the top, and another of immense ones at the base. Many of 

 these contain Amm. Berryeri like those of the region above, but 

 Amm. serratus is also plentiful. Blue clay, 20 feet thick, lies above 

 these latter doggers, and in places it is really difficult to say whether 

 the fossils or the clay compose the greater part of the bed ; but the 

 fossils are difficult to preserve and much broken. The fossils ob- 

 tained here are : — 



Ammonites Berryeri, Les. 



■ serratus, Sow. 



decipiens, Sow. 



hector, D'Orb. 



Astarte Michaudiana, D' Orb. 

 Area rhomboidalis, Cont. 

 Nucula Menkii, Bom. 

 Corbula Deshaysea, Buv. 

 fallax, Cont. 



Homomya compressa, Ag. 

 Ceromya orbicularis, Bom. 

 Pecten Grenieri, Cont. 



• arcuatus, Sow. 



Lima sedilignensis, Bla. 

 Anomia Dollfusii, Bla. 

 Ostrea, sp. 

 Lingula ovalis, Sow. 

 Discina elevata. Bla. 



At Langton less of the clay is seen before reaching the doggers ; 

 but this would seem to arise from the fact that there are many 

 rows of doggers in the clay, and the brick-pits are excavated till 

 the first is reached, since they always lie at the base. The doggers 

 here are brown when exposed to the air, being more or less ferrugi- 

 nous. The assemblage of fossils is remarkable — Rostellaria mosensis, 

 as mentioned before, being abundant, with Nucula obliquata, which 

 also belongs to a higher part, yet associated with several fossils 

 (Serpula tetragona, Cyprina cyreniformis, and Avicula cedilignensis) 

 which become common in the beds below. The species are : — 



Ammonites Berryeri, Les. 



serratus, Sow. 



Bostellaria mosensis, Buv. 

 Nucula Menkii, Bom. 



obliquata, Bla. 



Area rhomboidalis, Cont. 



Avicula sedilignensis, Bla. 



dorsetensis, Bla. 



Cyprina cyreniformis, Bla. 

 Pecten demissus, Ph. 

 Serpula tetragona, Sow. 



A small pit on the Caistor Road, near Market Rasen, which, 

 from its stratigraphical position, is lower than those before men- 

 tioned, seems, from its fossils, to be most comparable with that of 

 Baumber, i. e. by the large Amm. Berryeri and abundant Lingula 

 ovalis; but its more numerous Market-Rasen fossils associate it 

 more closely with the pits there. Here are found : — 



