﻿80 MR. S. S. BTJCKMAN ON CERTAIN [Feb. IQIO,. 



However, in Dorset-Somerset the strata which it is suggested 

 should be dated as Ancolioceras are those above scissum and below 

 the anglica horizon. 



In the Cotteswolds, there is between the Sandy Ferruginous Bed 

 (scissum) and the Pea Grit (murchisonce) a considerable development 

 known as the Lower Limestone : it is suggested that this should 

 be dated Ancolioceras. 



Various species of Ammonites of which the horizon has been 

 given ' near base of limestone-beds/ and the date as murchisonce or 

 doubtful between murchisonce and scissi, are presumably more 

 correctly to be dated as Ancolioceras hemera: for instance, the 

 following species : — Ancolioceras cariniferum, A. substriatum, 

 possibly A. costaium, Geyeria fasciata, and G. evertens. Investi- 

 gation will probably reveal others, which in former days were 

 recorded under the too comprehensive term Ludwigia murchisonce. 



Moorei, Dumor tier ice. — The strata of these dates make a fine 

 showing in the cliffs of the Dorset coast as the Bridport Sands x 

 and Down Cliff Clay : thej T attain a thickness of nearly 200 feet. 2 

 The Bridport Sands and the subjacent clay are represented around 

 Yeovil in Somerset by the Yeovil Sands, which are also of consider- 

 able thickness and have yielded many species of Dumortierice, as at 

 Yeovil Junction, Furzy Knaps near Yeovil, Bradford Abbas, etc. 

 The Ham Hill Stone is a local development of calcareous beds of 

 moorei date. 



The Yeovil Sands have suffered denudation, because around 

 Yeovil they end with the Dew (Dhu) Bed, which contains Dumor- 

 tierice like those in the moorei bed of Chideock Quarry Hill. Some- 

 where 'between Crewkerne and Yeovil the failure of the aalensis- 

 scissi beds begins. 



In the neighbourhood of Ilminster, Barrington, and Shepton 

 Beauchamp, the Yeovil Sands rest upon clay of dispansi date : in 

 these places the strata of variabilis date are a thin development 

 of clayey limestones very well charged with Ammonites.* 



Around Yeovil the sands become bluish and clayey in their lower 

 part : this may be of dispansi date. But the argillaceous limestones 

 of the Upper Lias on which this blue part rests gives no certain 

 evidence for later date than striatulus; the principal strata are 

 falcifer, bifrons, striatulus, all thin, without variabilis. The same 

 beds are found at Glastonbury Tor ; there is no sign of variabilis 

 forms among the fossils lying about in the fields. 



The deposit of sands between Yeovil and the Mendips presents a 

 field not yet investigated. When the Somerset & Dorset Railway 

 was made, a cutting in the sands at Cole Station near Bruton 

 (Somerset) yielded some fine specimens of Hammatoceras and Lyto- 

 ceratoids. I obtained a few of these, many years afterwards, by 



1 Excepting the upper 40 feet which are aalensis to scissi. See fig. 4, p. 70, 

 showing the Bridport Sands of Burton Bradstock. 



2 210 feet, teste B. C. H. Day, possibly including the upper 40 feet. 



3 See Monogr., Haugia-Lillia series. 



