154 CARBONICOLA, ANTHRACOMYA, AND NATADITES. 
1. CoaL-FIELD OF CoALBROOKDALE. 
Chance Pennystone With Productus scabriculus, Conularia, and Megalichthys. 
Fungous Coal 
Blackstone Coal and Ironstone Said to contain Unios. 
Ballstone Plant and fish remains. 
Top Coal | With a few Unios. 
Half-yard Coal 
Double Coal 
Yellow flat Ironstone 
Yard Coal A few Unios and fishes. 
Blue flats Ironstone With Carbonicola aquilina, C. ovalis, C. acuta, C. turgida, and plant 
remains. 
White flats Ironstone With Carbonicola aquilina, C. ovalis, C. turgida, C. acuta, Naiadites 
modiolaris, N. quadrata, and Crustaceans ( Bellinurus and Prestwichia). 
Flint Coal With Unio-like bivalves. 
Pennystone Ironstone With marine shells and Carbonicola robusta, C. ovalis, C. acuta, and others 
(Prestwich), and dnthracomya dolabrata. 
Stinking or Sulphur Coal 
Clunch Coal > 
| 
Best Coal | — + Many plant remains. 
| 
J 
Randle and Clod Coal 
Little Flint Coal -| With plant remains. 

Crawstone With Naiadites carinata, N. triangularis, and Anthracomya modiolaris. 
Nore.—In Professor Prestwich’s monograph the name Unio is given to Carbonicola, Anthracomya, and Sanguino- 
lites, so that it is uncertain, where Unio-like shells are said to occur in a bed without specific name, as to which of these 
genera they belong. In the list, however, at pp. 491, 492 of his work marine shells are stated to occur only in the 
Pennystone and Chance Pennystone beds. 
