322 GEOLOGY OF THE BEISTOL COAL-FIELD. 



Clifton beds of fossils. It is about a foot thick, and is extremely 

 rich in Brachiopoda and the sculptured defensive spines of 

 Oracanthus. The best opportunity for examining it was a short 

 time ago when an excavation was being made for a house in Sneyd 

 Park, on the road to Stoke Eishop. The limestone weathers easily, 

 and being rather argillaceous the various specimens are more easily 

 and perfectly separated from the matrix than they generally are. 

 The collector should look out for Rhynchonella acuminata and 

 Spirifera Mosg^uensis, which are great rarities. 



Oraca7ithis 2)ustulatus{Kg.), Millerii, (Ag.), minor {k^.), Terehratula 

 hastata {Sow.), T&r.ficus, (McCoy.), var.s«c^M^M5 (Mont.), y. vesicular is 

 (DeKon.); Rhynchonella acuminata {Sow.):, Spirifera Mosquensis{\)eiY.) 

 glalra (Dav.) duplicicostata (Dav.) Streptorhyncus crenistria (Dav,), 

 V. arachnoidea (Dalm.) ; Strophomena analoga (Phill.), Orthis 

 resupinata (Mart.) ; Cypricardia rhomlea (Mus. Pr. G.), parallela 

 (Phill.) ; Capulus vetustiis (Montf,) ; Euomphalus Bionysii (Goldf.) 



14. — [668]. — Spirifer hed. — This bed is instantly recognised by 

 the abundance of fine specimens of Spirifera striata that occur. It 

 is several feet thick and very dark in colour, and is the last 

 illustrative bed of the true Lower Carboniferous Shales that we 

 shall notice. It must not however be supposed that the intervening 

 strata are unfossiliferous. On the contrary the whole of the set of 

 beds is extremely rich, especially in Brachiopoda, so much so that 

 it is extremely difficult to select any special ones. The one now 

 under consideration may be recognised as the commencement of the 

 Black Eock Quarry, and contains chiefly — 



Psammodus porosus (Ag.) ; Spirifera striata (Dav.), var. attenuatay 

 cuspidata (Mart.); Producta punctata (Mart.), pustulosa (PhiU.) ; 

 Athyris Eoyssii (Dav.). 



Mountain Limestone. 



It is difficult and arbitrary to draw any line of demarcation in 

 the Clifton section, so gradually does one part pass into the other. 

 "We have, however, for convenience of description, commenced the 

 massive mountain limestone with what is locally known as the 



