Vol. 6o.l SECTIONS IX THE BRISTOL DISTRICT. T89 



the older records of Wright (2). Even in the north, the succession 

 may be fairly-well made out by combining sections at Gainsborough, 

 Leicester, and Market Weight-on, except that Pleuromya is recorded 

 with Monotis decussata above it. 



(ii) These zones do not fit in with the oceanic type of the Alps 

 and Mediterranean — a harmony which, however, could scarcely 

 have been hoped for. But they receive considerable support from 

 the German, and less perhaps from the French sections, at any rate 

 in the lower four members. 



Especially well do they harmonize with some German sections 

 described by Schlonbach (57 & 58), as, for example, at Steinloh and 

 Salzgitter. Here are recorded, in descending order : — 



b. Layer with plant-remains. 



'-/'. (Fossils not mentioned.) 



q. • Upper Bone-Bed' : in which Pecten cloacinus (=P. valoniensis) 



and Avicula contorta are described by Quenstedt (56). 

 r. Black Shales, with Avicula contorta. 

 s. ' Lower Bone-Bed/ conglomeratic. 

 t. Greenish-grey marl. 



V. Summary. 



I. Descriptions of sections : 



(a) At Redland, distinguished by a bone-bed and an excellent suite of 



fossils. 

 ib) At Stoke GifFord, with an insect-bed, but no bone-bed. 



(c) At Cotham Boad, with an excellent Black-Shale fauna, and well- 



developed Xaiadita-Heds. 



(d) At Aust. 



II. The Bone-Bed is a storm-deposit in very shallow water and 

 over exposed flats. 



III. The Bhoetic Beds of England were laid down in a vast, verv 

 shallow lagoon or bay, and derived their fauna from Germany. 



IV. The English Rhaetic presents more affinity for the Jurassic 

 than the Triassic. 



V. The following zones may be recognized : — 



1. Zone of Pleuromya Crowcombeia = {^^^f 1 Blue Lias> 



2. .. Monotis decussata=: Cotham Marble and just above. 

 o. „ Estheria minuta var. Brodieano, and Xaiadita. 



4. „ Tecten valoniensis. 



5. ,, Avicula contorta — Black Shales and a limestone-bed. 



6. ., Bone-Bed. 



The pleasantest page in this paper is to me the one on which 

 I now record my sincere and hearty thanks to all those to whose 

 kindness, consideration, and help I owe so much. Especially am I 

 grateful to Mr. Arthur Vaughan, F.G.S., for directing my attention 

 to various memoirs, and for some suggestions as to "fossils • to 



