﻿Vol. 64.] CARBONIFEROUS LIMESTONE OP THE MIDLAND AREA. 43 



Brachiopods : 



Athi/ris cf. expansa (Phil.). Productus aff. giganteus (Mart.). 



Martinia glabra (Mart.). Productus aff. pustuloms, Phil. 



Cyrtina septosa (Phil.). Productits punctatus (Mart.). 



Orthothetes cf. crenistria (Phil.). | Productus aff. concinnus, Sow. 



Productus aff. corrugatics, M'Coy. i Papilionaceous Chonetes. 



Productus corrugato-hemisphericus. \ Baviesiella aff. comoides (Sow,). 



Productus hemisphericus, Sow, i 



This subzone includes all that part of the limestone series which 

 underlies the upper toadstone, in the typical section, and its total 

 thickness is estimated at 950 to 1000 feet. Considered as a whole, 

 the subzone is poorly fossiliferous ; but the uppermost beds contain 

 corals in considerable abundance. The lowest beds, about 150 feet 

 in thickness, have not yielded any corals. They contain, however, 

 Productus aff. giganteus and Baviesiella aff. comoides^ brachiopods 

 which occur throughout the subzone, and they have not yielded any 

 distinctive fossils. I therefore include them in the Dihunophyllum 

 0-8ubzone. 



Paunal characters (excluding the lowest beds referred to 

 above) : — 



BihunopliylJa of a simple type occur rarely throughout the 

 main part, and commonly at one or two levels near the top of the 

 subzone. 



Diphyphyllum lateseptatum is common in the uppermost beds. 

 Lithostrotion junceum, Syringopora cf. distavs, and S. cf. geni- 

 culata are abundant at the same level, but uncommon at lower 

 horizons. Lithostrotion Martini occurs sparingly throughout the 

 main part of the subzone and more commonly in the upper beds. 



Cyathophyllum aff. Murchisoni (?) and Alveolites are somewhat 

 rare in occurrence. A single specimen of Carcinophylluni aff. 

 has been recorded. 



Productus aff. giganteus occurs throughout, but is never very 

 abundant. The specimens do not attain any great size, and 

 show no such extraordinary variation as is exhibited in the suc- 

 ceeding subzone. The typical form of Productus giganteus has 

 not been recorded in this subzone. 



Baviesiella aff. comoides, in a form closely similar to that which 

 characterizes D^ in the South- Western Province, occurs very 

 commonly at certain levels. 



All the other brachiopods and corals included in the faunal 

 list are of rare occurrence. 



Few sections in the area, other than the typical section, afford 

 any vertically-extensive exposure of this subzone : and the foregoing 

 account of faunal characters is based almost entirely on the obser- 

 vations made in the examination of the typical section. The large 

 quarries at Peak Forest and Doveholes, north of Buxton, show fine 

 exposures of the massive white limestones which form a part of the 

 subzone, but I have not examined these sections in detail. Among 



