APPENDIX I.—AMMONITES FROM THE SCARBOROUGH LIMESTONE.

Abstract

The strata which Quenstedt called the Coronaten-schichten, the strata of the Blagdeni zone (formerly Humphriesianum zone, in part) are only well-developed in the South of England in the neighbourhood of one locality, Sherborne, in Dorset, where they are very fossiliferous. But their preservation is very local, even close around the town.1 Southward some 20 miles, at Burton Bradstock, there is some evidence for these strata2; but from Sherborne northwards to Yorkshire, a distance of nearly 300 miles must be travelled (and more along the Inferior Oolite outcrop) to find the next place where the Coronaten-schichten have been preserved. Over most of that long interval it is known that these strata have been removed by pene-contemporaneous erosion. It is just possible that the Hibaldstow beds of the Lincolnshire Limestone may be a deposit of this date;3 but they are almost worthless to the palaeontologist. The Scarborough Limestone yields some Ammonites which fix its date—this has been long known from the species figured in Morris and Lycett’s work.4 As deposits of this date are so rare in this country, and as Mr. Richardson has submitted certain specimens which the authorities of the Scarborough Museum have kindly forwarded to him, and others which Mr. R. S. Herries kindly lent him, it may not be without interest to review the evidence. 1. Skirroceras ? triptolemus, Bean MS. sp. Ammonites triptolemus, Bean MS. teste Morris and Lycett. 1850. Ammonites braikenridgii. Morris and Lycett (non Sowerby), Great Ool. Moll., (Pal. Soc.) p. III, PI. XIV, …