ON A NEW LABYRINTHODONT AMPHIBIAN. 219 



VIII. — On a new Labyrinthodont Amphibian from the Magnesian 

 Limestone of Midderidge, Durham. By Albany Hancock, 

 F.L.S., and Richard Howse.* (Plate VI.) 



Among the important additions to the fauna of the Permian rocks 

 of Durham made by Joseph Duff, Esq., last autumn, not the 

 least interesting, perhaps, may be reckoned the remains of a 

 Labyrinthodont having numerous finely striated, rhombiform 

 scutes or scales, resembling in shape those of some Ganoid fishes, 

 though very superior in size. These remains were found at the 

 Midderidge quarry (a portion of which has recently been removed 

 for the purpose of widening the Darlington and Wear Valley 

 Railway), in a bed of yellow marly limestone seven or eight feet 

 above the Marl-slate properly so called. The section at this 

 quarry is thus described by Prof. Sedgwick, Geol. Trans., Ser. 

 II., Vol. III., p. 76:— 



"1. Bed of light-coloured siliceous sandstone, worked as a 

 coarse flagstone and also as a building-stone. The upper beds 

 alternate with blue-coloured calcareous shale. At East Thickley 

 they are about thirty feet thick. 



"2. Yellow -coloured calcareous shale and shale -slate, in 

 thickness about nine feet. Some of these beds are incoherent 

 and sandy ; the Marl-slate forms a series of indurated bands, 

 which divide the more incoherent shale. 



"3. A series of thin beds with marly partings; the whole 

 about twenty feet thick. The average thickness of the several 

 beds is not more than a few inches ; their surfaces are often 

 covered with yellow marl ; at their natural partings they are 

 generally covered with dendritical impressions," etc. 



In the above section, No. 1 represents the uppermost member 

 of the Coal Measures, which in this part of Durham have been 

 much disturbed and denuded prior to the deposition of the Marl- 

 slate. It must be mentioned that in this quarry and in the south 

 of Durham there is no bed of " yellow incoherent sand," a bed 



* This and the two following papers are reprinted by permission of the Council of the 

 Geological Society (from Vol. XXVI. of their "Proceedings") who have also kindly granted 

 the use of the plates illustrating the papers. 



