2/2 THE OLDEST AIR-BREATHERS 



ing whether they retained the superficial markings of Sigillariae, 

 and with reference to the fossils contained in them. It was 

 while examining a pile of these " fossil grindstones " that we 

 were surprised by finding on one of them what seemed to be 

 fragments of bone. On careful search other bones appeared, 

 and they had the aspect, not of remains of fishes, of which 

 many species are found fossil in these coal measures, but 

 rather of limb bones of a quadruped. The fallen pieces of the 

 tree were carefully broken up, and other bones disengaged, and 

 at length a jaw with teeth made its appearance. We felt quite 

 confident, from the first, that these bones were reptilian ; and 

 the whole, being carefully packed and labelled, were taken by 

 Sir Charles to the United States, and submitted to Prof. J. 

 Wyman of Cambridge ; who recognised their reptilian char- 

 acter, and prepared descriptive notes of the principal bones, 

 which appeared to have belonged to two species. He also 

 observed among the fragments an object of different character, 

 apparently a shell ; which was recognised by Dr. Gould of 

 Boston, and afterward by M. Deshayes, as probably a land- 

 snail, and has since been named Pupa vetusta. 



The specimens were subsequently taken to London and re- 

 examined by Prof. Owen, who confirmed Wy man's inferences, 

 added other characters to the description, and named the 

 larger and better preserved species Dendrerpeton Acadianum, 

 in allusion to its discovery in the interior of a tree, and to its 

 native country of Acadia or Nova Scotia. It is necessary to 

 state in explanation of the fragmentary character of the remains 

 obtained, that in the decay of the animals imbedded in the 

 erect trees at the Joggins, their skeletons have become disar- 

 ticulated, and the portions scattered, either by falling into the 

 interstices of the vegetable fragments in the bottom of the 

 hollow trunks, or by the water with which these may have 

 sometimes been partly filled. We thus usually obtain only 

 separate bones ; and though all of these are no doubt present 



