ON THE OCCURRENCE OF LOXOMMA ALLMANNI. 201 



remains. However it may be with Rhizodus, it would therefore 

 seem impossible not to adopt the conclusion that all these speci- 

 mens belong to one and the same fish ; and the tooth proves 

 that they do not belong to Rhizodus. For this fish, then, so 

 characterised, and which seems to us to be generically as well 

 as specifically new, we propose the name Archichthys sulcidens. 



We must add, before concluding this note, that the teeth of 

 our new fish sometimes measure two and a half inches in length, 

 and are upwards of an inch wide at the base, and that upwards 

 of a score of specimens of it have occurred at Newsham. It is 

 therefore pretty certain that they never attain the dimensions of 

 those of Rhizodus, from which they can always be distinguished 

 by their rotundity, the total absence of cutting-edges, and the 

 fine striation of the surface ; though they are folded at the base 

 in a manner similar to those of that great enigma. 



We may also add that thirteen opercular plates have been 

 found, some being quite perfect and in excellent condition. The 

 scales, too, are not by any means rare in the same locality. 

 The remains, then, of this fish being so abundant, the non-occur- 

 rence of the large Rhizodus-tooth is very significant. 



VI. — On the Occurrence of Loxomma Alhnanni in the Northum- 

 berland Goal-Field. By Albany Hancock, F.L.S., and Thos. 

 Atthey. 



A few months ago we announced the occurrence in the Coal- 

 shale, near Newcastle, of a considerable portion of the cranium 

 of Anthracosaurus. We have now the pleasure of recording the 

 presence of another large Labyrinthodont Amphibian in the same 

 locality, Mr. Atthey having recently obtained, in the black shale 

 at Newsham, a nearly perfect skull of Loxomma Alhnanni, Hux- 

 ley, which we believe to be the first authenticated specimen of 

 this fine Labyrinthodont that has been found in this neighbour- 

 hood. 



The skull is complete, with the exception of the muzzle, which 



