'90 AIR-BREATHERS OF THE COAL PERIOD. 



" The contents of the trunk correspond with those of others pre- 

 viously found. At the bottom is the usual layer of mineral char- 

 coal, consisting of the fallen wood and bark of the tree itself. Above 

 this, about two feet of its height are filled with a confused mass of ve- 

 getable fragments, consisting of Cordaites, Lepidodendron, Teloden- 

 dron, Lepidostrobus, Calamites, Trigonocarpum, stipes and fronds 

 of ferns, and mineral charcoal; the whole imbedded in a sandy 

 paste blackened by coaly matter. In, and at the top of this mass 

 occur the animal remains. The remainder of the trunk is oc- 

 cupied with grey and buff sandstone, containing a few fragments 

 of plants, but no remains of animals. 



" Portions of six reptilian skeletons were obtained from this trunk. 

 The most important of these is a large and nearly complete skele- 

 ton of Dendrerpeton Acadianum.* Another specimen found in 

 this trunk is a jaw of an animal about the size of Dendrerpeton 

 Acadianum, but with fewer and larger teeth.f The remaining 

 skeletons were imperfect, and belonged to a small individual of 

 Dendrerpeton Acadianum, two of Hylonomus Lyelli, and one of 

 Hylonomus Wymani. The dislocated condition of these and 

 other skeletons is probably due to the circumstance that, when 

 they were introduced, the matter filling the trunk was a loose mass 

 of fragments, into the crevices of which the bones dropped, on 

 decay of the soft parts. Most of the skeletons lie at the sides of 

 the trunk, as if the animals had before death crept close to the 

 walls of their prison. At the time when the reptiles were intro- 

 duced, the hollow trunk must have been a pit four feet in depth. 

 A number of specimens of Pupa vetusta and Xylobius Sigillarice, 

 were found, but nothing throwing further light on these species. 



" The beds on a level with the top of this erect tree are arena- 

 ceous sandstones, with numerous erect Calamites. I searched the 

 surfaces of these beds in vain for bones or footprints of the rep- 

 tiles which must have traversed them, and which, but for the hol- 

 low erect trees, would apparently have left no trace of their exis- 

 tence. On a surface of similar character, sixty feet higher, and 

 separated by three coals, with their accompaniments, and a very 

 thick compact sandstone, I observed a series of footprints, which 

 may be those of Dendrerpeton or Hylonomus? 



* Now in the collection of the Geological Society of London. Fig. 1, 

 represents the skull of this specimen. 



f Since named and described by Prof. Owen as Hylerpeton Dawsoni. 



