1 10 Preston : Lincolnshire Naturalists at Scunthorpe. 



and it will be discontinued when the Keuper Marls pass wholly 

 into the New Red Sandstone, when the bore will be 10 inches 

 across. Geologically the bore section is ot "threat interest, seeing 

 that, after passing through about 19 feet of alluvium, the Rhcetie 

 beds were touched at their outcrop, at the foot of the cliff. The 

 section was but a few inches thick, and occurred only on the east 

 side of the well ; but the black shales and pyritous bed with 

 coprolites and small fragments of what appear to be fish spines 

 or teeth were quite sufficient to fix the horizon of these interest- 

 ing beds. The cores brought up after passing the Rhcetics 

 consisted of red and blue marls, with varying amounts of 

 gypsum, which continued down to 676 feet, the depth of bore 

 at the time of visit. It is intended to sink to a depth of 

 1,600 feet, so as to penetrate some 700 feet or more into the 

 Bunter Sandstone. There is no doubt that when the bore 

 and works are finished this district will have an excellent and 

 abundant supply of water, and the visitors were extremely 

 pleased that Mr. Cobban had given them the opportunity of 

 seeing the work now in progress. Walking from this bore-hole 

 in an easterly direction the party climbed the escarpment, about 

 150 feet high, formed by the limestone beds of the Lower Lias, 

 and examined an interesting section, 17 feet deep, for the new 

 gas works. This section is in the Gryphaea Zone, a sub-zone 

 of the Bucklandi zone of the Lower Lias; and the characteristic 

 fossils — Gryphcea incurva, Ammonites bucklandi, Lima gigantea, 

 etc. — were found. Proceeding thence through the town various 

 points of outcrop of the Ironstone were shown, and a visit was 

 made to the Trent Ironstone Mines, where a face of workable 

 ironstone 20 feet thick was seen. The ironstone is overlaid 

 directly by sands and peat, but in one part of the pit a section 

 of the clay was also seen which comes immediately above the 

 ironstone. In this clay numerous concretionary nodules occur 

 which are interesting to the fossil collector, many of them 

 containing Ammonites and other fossils in a good state of pre- 

 servation. Numerous fossils occur in the ironstone, and a good 

 list were noted, including Ammonites semicostatus, A. conybeari, 

 A. bucklandi, Belemnites , Pleurotomaria anglica, Nautilus, 

 Cardinia listeri and two other species, Pholadomya ambigua, 

 Lima gigantea, L. pectinoides, Pecten cequalis, P. cequivalvis, 

 Gryphcea incurva, Rhynchonella, Spiriferina isoalcotti, crinoid 

 stem, Ichthyosaurus (vertebra), and fossil wood. 



The ironstone forms the upper part of the Bucklandi Zone 

 and is styled the Semicostatus Zone because of the prevalence of 



Naturalist, 



