208 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [DeC. 14, 



Labyrinthodont Batrachia, e. g, Trematosaurus, Capitosaurus, and 

 Labyrinthodon proper. The evidence of this structure presented by 

 the tubercles of carbonaceous matter that filled the depressions in the 

 bone, is at the same time evidence of the pulpy or plastic state of 

 the carbonaceous matter when it made the cast of the sculptured 

 outer surface of the cranium, which surface it now shows in relief. 



A small microscopic section of the osseous tissue, which Mr. 

 Quekett has had the kindness to prepare, shows very distinct and . 

 well-defined bone-corpuscles or cells, of an elliptic or oval figure, 

 scattered throughout the tissue, at distances of from one to two or 

 three of their own long diameters : without any appearance, in the 

 section prepared, of vascular canals. The size of these bone-cells is 

 less than those in the Batrachian reptile discovered by Sir Charles 

 Lyell and Mr. Dawson in the South Joggins coal-field of Nova Scotia*, 

 and corresponds with those in some of the larger Sauria, as e. g. the 

 Megalosaurus. Neither Mr. Quekett nor I have yet met with any 

 fish-bone recent or fossil, which shows a microscopic structure like 

 that of the fossil in question from Pictou coal. 



From the characters above specified, therefore, I conclude that this 

 fossil is the fore-part of the skull of a Sauroid Batrachian, of the 

 extinct family of the Labyrinthodonts. It agrees with them in the 

 number, size, and disposition of the teeth ; in the proportions and 

 mode of connexion of the premaxillaries, maxillaries, nasals, pre- 

 frontals, and frontals ; and in the resultant peculiarly broad and 

 depressed character of the skull. The traces of the nostrils are less 

 definite and satisfactory than the remains of the orbits ; but the 

 latter appear to me to be decisive against the piscine nature of the 

 fossil. The fossil also presents the same well-marked external sculp- 

 turing as in the Labyrinthodonts; and amongst the genera that have 

 been established in that family, the form of the end of the muzzle, 

 or upper jaw, in the Pictou coal specimen best accords with that in 

 the Capitosaurits and Metopias of Von Meyer and Burmeister. 

 [The orbits have been evidently larger and of a different form than 

 in the reptiles so called ; and, tor the convenience of distinction and 

 reference, I propose to name the present fossil Baphetes pla?uceps 

 (/joTTT-w, I dip or dive), in reference to the depth of its position, its 

 probable diving habits, and the shape of its head. — Feb. 25, 1854.] 



4. On the Tracks of a Crustacean in the " Lingula Flags." 

 By J. W. Salter, F.G.S., A.L.S., of the Geological Survey of 

 Great Britain. 



While investigating in the past autumn the fossil contents of the 

 lowest fossiliferous zone in Wales — the "Lingula flags " — my atten- 



* See Quait. Journ. Geol. Soc. vol. ix. \i\. 3. fig. 8. 



