of Derbyshire and Notts Coalfield. 



29^ 



Carhonicola niicularis, Hind 



C. turgida, Browa 



C. aquilina, Sow. 



C. acuta, Sow. 



C. acuta, var. rhomhoidalis, Hiud 



Naiaditcs modio/arts, J. de C. Sow. 



Anthracomya modiolaris, Sow. 



A. cf. leevis, Dawson, var. scotica, 



R. Eth., jim. 

 Spirorhis sp. 



L'uigula mytihrides, Sow. 

 Spirifer sp. 



Ptcrvnoj)ecten papyraceus, J. Sow. 

 Posidoniclla minor, Brown 

 P. leevis. Brown 

 Gastrioceras Listeri, Mart. 

 G. carhoiiarinm, Von Bueli 

 G. coronatnni. 



Glyphioceras bilingue{?), Salter 

 Binxorphoceras Gilbertsoni, Phill. 

 Pleuronautilus sp. 

 Orthoceras (more than one species) 

 Gasteropoda (of several species). 

 Acanthodes Wardi, Egert. 

 Sphenacanthns hyboides, Egert. 

 Ccelacanthus elcgans, Newb. 

 Megalichthys Hibberti, Agass. 

 M. intermedins, A. S. Woodw. 

 Rh{zodoj)sis sauroides. Will. 

 Elonichthys Aitkem, Traq. 

 E. Binneyi, Traq. 

 Platysomus tenuistriatus, Traq. 

 Rhadinichthys monensis, Egert. 

 Mesolepis scalaris. Young 

 M. micropteriis, Traq. 

 Hoplouchns sp. 



DlSTKIBUTlO^r OF THE FoSSILS. 



The scarcity of exposures in this area, and the difficulty of 

 attaching names to some of the specimens owing to the unsatisfactory 

 state of our present knowk'dge of the Cephalopoda and Gasteropoda 

 of the Coal-measures, combine to render the list of fossils only a 

 partial indication of the life of tlie period. Within such a relatively 

 small thickness of measures there is no restriction of particular species 

 to definite horizons. 



Plants. — The few plants are all common species ; they occur chiefly 

 in association with the coal-seams, and in the sandy beds of the 

 Wingfield Flagstones. 



Fish. — Fragmentary scattered fish-remains occur in almost all the 

 shales; they become numerous in the roof-shales of the Kilburn, 

 Naughton, and Alton Coals, forming thin bone-beds composed of 

 scales, teeth, bones, and spines. 



The bands of concretionary nodules of clay ironstone, locally called 

 ' Rakes', have in the past yielded numerous perfect specimens of fish. 



Remains of fish are usually found not to extend over wide areas. 

 Of these fish-beds, only that in the marine bed over the Alton Coal is 

 persistent throughout and beyond this district; its range would 

 appear to be coextensive with that of the marine bed. Although no 

 attempt has been made to show its persistence in other areas, it has 

 been several times observed in the equivalent marine bed of the 

 Lancashire, North Staffordshire, and Yorkshire Coalfields. 



Freshwater {or Estuarine') Mollusca. — The zone fossil for this 

 sequence and the succeeding measures up to the Deep Hard Coal is 

 Carhonicola robusta. The range of C. micularis is a little wider, 

 but outside the zone of C. rohusta it is very rare. The specimens 

 of C. acuta are sometimes dwarfed, and similar dwarfed C. acuta have 

 been recorded from the Ganister series of other coalfields (H). 



It is interesting to observe (see Fig. 1) that at least one of these 

 ' Mussel Beds ' is persistent for some distance, forming a definite 

 horizon of local value in the identification of shaft sections. 



Marine Fauna. — With the exception of a bed containing only Lingula 



