222 NORTH STAFFORDSHIRE COAL FOSSILS. 



more complete specimens showing the whole of the dental 

 series have been found. 



Position and locality : Deep mine, Knowles, and Chalky 

 mine ironstones, Fenton and Longton ; Gubbin ironstone, 

 Hanley ; Brown mine, Silverdale ; Ash coal shale, Fenton. 



GENUS JANASSA, MUNSTER. 



Janassa ling ucefor mis, Atthy. (Climaxodus linguajformis, 

 Hancock and Atthy), (Ref., Ann. Nat. Hist., series 4, vol. ii., 

 p. 321). A single tooth of this rare genus has occurred at 

 Longton. The length is greater than the width, and the 

 tooth tapers behind. The front has a wide scoop-like 

 margin ; behind this, the surface is covered with imbricated, 

 transverse ridges, which form the grinding edge of the 

 tooth. (See plate, fig. 8.) 



Position and locality : Deep mine ironstone, Longton. 

 GENUS PLEURODUS, AGASSIZ. 



Pleurodus Rankinii, Ag. (Rcf., Poiss. Foss., vol. 

 iii., p. 174.) Single teeth of this species are not 

 unfrequently found in the Hard mine coal shale. The 

 teeth are somewhat boss-like in form, " elongated and ridged 

 or carinated along the longer axis : the sides are considerably 

 expanded in the centre, the expansions dying out towards 

 the centre of the tooth. Usually the expansion is more 

 produced on one side than on the other, and the ridges 

 inclined to the opposite side." * A specimen has recently 

 been found in the Northumberland coal-measures showing 



* Annals of Nat. Hist., vol. for 1872. 



