224 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 6, 



a great valley of elevation, the line of the volcanos being its anti- 

 clinal line. 



Mr. Malcolmson and others have established the age of certain 

 beds connected with the eastern margin of the trap. Dr. Leith's dis- 

 covery bids fair to determine the age, on the western margin, of the 

 beds above the regular trap and below the basalt capping. 



Professor Orlebar is of opinion that he has discovered a sort of in- 

 tercalary volcano, below this basalt, in Salsette. 



I have collected a great number of specimens, and I hope, during 

 the next eight months, when I shall be under canvas, to add to them, 

 and so far to arrange them as to render them worth the acceptance of 

 the Society, when perhaps some competent geologist may be induced 

 to take the matter up. 



4. On the Batracholites, indicative of a small species of Frog 

 (Rana pusilla, Ow.). Addendum to the Communication from G. T. 

 Clark, Esq., Bombay. By Professor Ow^en, F.G.S. 



The portions of shale transmitted by Mr. Clark contain delicate, but 

 for the most part distinct, traces of the, generally, entire skeleton of 

 small anourous Batrachia ; the osseous substance is black, as if 

 charred. 



The number of vertebrae, atlas and sacrum inclusive, is nine : the 

 caudal vertebrae are fused into a long, slender cylindrical style, as in 

 most anourous Batrachia. 



Fig. 1. Fig. 2. 



In the specimen (fig. 1) which lies on its back, the posterior 

 convexity of the vertebral bodies is shown. 



The short, subcylindrical and very slightly expanded lateral or trans- 

 verse processes of the sacrum, and the absence of ribs or their rudi- 

 ments in the dorsal vertebrae, with the proportional expanse of the 

 skull and length of the hind-legs, show the specimens to belong to 

 the family of Frogs (Ranidce) . 



There are seven abdominal vertebrae, with long and subequal trans- 

 verse processes, that of the second (third vertebra including the atlas) 

 being the longest. The humerus is cylindrical, not expanded as in 



