Mr Pentland on a Collection of Fossil Bones 121 



A careful inspection of the specimens of Major MitcheH's 

 Collection, leaves not a doubt that the bones of most of the ani- 

 mals collected in these caves, were transported thither by carni- 

 vorous animals, as in our bone-caves of Yorkshire, of Germany, 

 of France, &c. I have discovered several fragments, evidently 

 gnawed and worn down under the teeth of small carnivorous 

 animals ; and, among nearly 100 specimens of long bones, still 

 enveloped in their stalactitic crust, I have not found one to 

 which the epiphysis remained attached, although in adult sub- 

 jects, — an evident proof of their having been gnawed off by the 

 animals which formerly inhabited these recesses. What these 

 animals were, it is easy to guess from the catalogue given in my 

 former and present communication. 



In addition to the fossil bones. Major Mitchell's collection was 

 accompanied by an interesting geological suite of the rocks of 

 the surrounding country, which enables me to add something to 

 what has been already published in your Journal, on the geo- 

 gnostical position of the bone-caves of Wellington Valley. The 

 rock in which these caverns is excavated, is a dark grey dolomi- 

 tic limestone, which, like all similar rocks, appears to have been 

 converted into that state subsequently to its deposition, under 

 circumstances analogous to those so ably pointed out by my 

 friend M. de Buch, in his remarkable papers on the Dolomites 

 of the Tyrol and of the Alps of Lombardy. The specimens 

 before me offer all the passages from a compact grey secondary 

 limestone to a semi-crvstalline dolomite, and the view of a con- 

 siderable mass of trap-rock, and of a large-grained pyroxenic 

 rock, leave scarcely a doubt that the dolomites of Australasia 

 owe their present form to changes similar to those which have 

 converted the secondary limestones on the southern declivity of 

 the Alps, into a crystalline dolomite, viz. the vicinity of pyroxe^ 

 nite eruptions. 



It is probable that the limestone thus converted into dolomite 

 is a continuation of that of Sass Plains, which contains fossil re- 

 mains of madrepores, and which offers certain analogies with 

 those of the oolitic series of the northern hemisphere, and which 

 appears to repose upon the new red sandstone formation, which 

 constitutes so large a proportion of the known portion of the 

 Australasian continent. — Yours, kc. 



