﻿Vol. 66.~] JURASSIC STEATA OF SOUTH DORSET. 65 



Thickness in feet inches* 

 falciferi (h) Attached to yellowish-blue, some- 

 what sandy stone. Harpoceras 

 falciferum and H. cf . strangwaysi. 8 



acuti or (?) Marlstone brown, finely ironshot. 



tenuicostati (?) In two beds. 

 (serrata-bed) In the upper bed : Rhynchonella 



serrata ; large, hollow - keeled 



Harpoeeratoid Ammonites and 



Thysanoceras. 



spinati (j) In the lower bed Rhynchonella 



{Rli. media bed), media (that is, the rotund* tetra- 



hedra form), Rh. acuta, Spiriferina. 1 3 



' 3 ** 

 (The thickness of the Junction Bed is 



thus 3 feet 3 inches, but it is never 



found complete : about 2 feet, with 



beds missing, is the rule.) 



Having come so far down the cliff in detail, it may not be 

 uninteresting to reproduce, with modern interpretations, the section 

 published by E. C. H. Day, which embraces the whole of it 

 (see fig. 3, p. 66). 



(b) Burton Bradstock. 1 



Eastward along the coast the cliffs east of West Bay up to Burton 

 Bradstock afford fine sections of Bridport Sands, capped in places 

 with Inferior Oolite : the latter, especially at Burton Bradstock 

 noted for its abundant fauna, can also be studied in quarries about 

 the village. The details of the stone beds — the Inferior Oolite — 

 differ greatly in a short distance : and therefore only a generalized 

 account of the succession is necessary. 



The Eullers' Earth Clay rests on a bed known to the workmen 

 as The Scroff — a thin irony layer yielding Oppelia fusca and 

 allied species. Like the striatuhis layer on the top of the Junction 

 Bed, it is often missing. 



The zigzag bed comes below the Scroff — it is confined to about 

 the top 6 inches of what the workmen call the 1st Bed, and is 

 recognizable by its bluish colour. The rest of this bed is a 

 different matrix : it is somewhat deficient in fossils ; but lithically 

 and faunally it seems to be the continuation of the bed below, which 

 the workmen call the 2nd Bed. Its yellowish colour, with earthy 

 partings, and its stout forms of often poorly preserved Parkinsonian 

 distinguish it. This 2nd Bed and the lower part of the first, 

 containing a fauna distinct from that of the zigzag bed above or 

 the truellii bed below, may be dated as hemera of Parhinsonia 

 schloenbachi, Schlippe. The 3rd Bed of the workmen contains two 



1 For other accounts of the strata of this locality, the reader is referred to 

 W. H. Hudleston, ' Monogr. Brit. Juras3. Gasteropoda ' (Palaeont. Soc), 1887, 

 pt. i, p. 31 ; H. B. Woodward, ' Juuassic Rocks of Britain : vol. iv — The Lower 

 Oolitic Rocks of England ' Mem. Geol. Surv. 1894, pp. 55 et seqq. ; also 

 S. S. Buckman, Quart. Journ. Geol. Soc. vol. xlv (1889) p. 451, and Proc. 

 Geol. Assoc, vol. xv (1898) p. 296. 



Q. J. G. S. No. 261. v 



