﻿190 DR. A. VAUGHAN Otf THE PAL2E0NT0L0GICAL [May 1905, 



Eumetria (' Retzia ') aff. carbonaria, Productus bassus, and Chonetes 

 cf. Buchiana are practically confined to this subzone. 



Syringothyris aff. cuspidata becomes common towards the top of the 

 subzone; but Spirifer spp., Spiriferina octoplicata, Ehipidomella, and 

 Productus cf. Martini are either absent or very rare. 



K 2 = Subzone of Spiriferina octoplicata (octoplicata- 

 subzone) . 



This includes the upper and main portion of the Cleistopora- 

 Zone, as well as the horizon of overlap with the Zaplirentis-Zone 

 (Horizon /3). 



Braehiopods: 



Leptena, Orthotetes, Chonetes cf. crassistria, and Ch. cf. hardrensis are still 

 abundant ; but Orthotetes shows a mutational change. 



Camarotmchia mitcheldeanensis is still common, but diminished in 

 numbers ; and Spirifer aff. clathratus becomes increasingly numerous as 

 we approach Horizon /3. 



Rhipidomella, Productus cf. Martini, and the mutation of Cliothyris 

 Royssii which is characteristic of the lowest subzone of the Zaphrentis-Tione 

 begin to make their appearance. 



Spiriferina octoplicata reaches its acme at the top of this subzone. 



Corals: 



Cleistopora aff. geometrica is nowhere common, but is most abundant in 

 the upper part of this subzone. 



Z = Zone of Zap/Mentis aff. Phillipsi (ZAPHHENTis-Zone) . 



Lithological character. — Massive limestones, usually very 



encrinital. 

 Former designation. — The Lower Limestone (omitting the 



uppermost beds). 

 Where exposed in the Avon section: — 



Clifton side : The Black Rock (see below, pp. 191-93). 



Leigh Woods side : Quarries 1 & 2 (see PI. XXVII). 



Coral-fauna: 



Zaphrentis aff. Phillipsi. 

 Zaphrentis aff. cornucopice. 

 Caninia cylindrica. 



Brachiopod-fauna : 



Cliothyris glabristria & mut. 

 Cliothyris Royssii & mut. 

 Spirifer aff. clathratus & var. 

 Reticularia aff. lineata. 

 Spiriferina octoplicata. 

 Syringothyris cuspidata, muts. 

 Syringothyris aff. laminosa. 

 Camarottxchia mitcheldeanensis, muts. 

 Camarottxchia cf. pleurodon. 

 Leptena analoga. 

 Schizophoria resupinata. 



Amplexus cf. coralloides. 

 Michelinia spp. 

 Syringopora 0. 



Orthotetes crenistria (especially 



mut. Z). 

 Rhipidomella aff. Michelini. 

 Productus cf. Martini. 

 Productus semireticulatus, muts. 

 Productus aff. pustulosis. 

 Productus aff. Cora mut. Z. 

 Chonetes cf. crassistria. 

 Chonetes cf. hardrensis. 

 Chonetes papilionacea. 



