THE VICTORIAN NATURALIST. 29 



by any vestiges of those typical groups of strata seen on the 

 Australian mainland and in Europe, as for instance in the Lias, 

 the Muschelkalk, Wealden, and true Chalk. 



Apart from the interesting Lahyrinthodon remains, the oldest 

 fossil bones as yet discovered in the colony, have no greater antiquity 

 than the close of the miocene epoch. These consist of bones and 

 teeth of Hypsypromnus, (Kangaroo Rat), found beneath a solid 

 sheet of basalt at One Tree Point by my friend Mr. R. M. 

 Johnston, F.L.S. &c , while working up the plant remains of the 

 island. 



Notwithstanding this comparatively recent character, they have 

 no small interest, as tending to throw some light on the antiquity 

 of existing indigenous mammals, both placental and implacental. 



There are not more than three or four caves known to contain 

 fossil bones in Tasmania — the great Chudleigh Cave in Silurian 

 limestone, another smaller one in the same district, distinguished as 

 the habitat of a new and singular cave-inhabiting spider, Tlieridon 

 Troglodytes, (Higgins and Petterd), and the Barradal Cave, Mt. 

 Fawkner, Glenorchy. To this latter my remarks will chiefly apply, 

 and which I was the first to explore immediately upon its discovery 

 being made known to me some years ago. 



My attention was drawn to it by a young friend of mine who had 

 just returned, with his companions, from a kangaroo hunting 

 expedition among the ranges of hills in the district of Glenorchy, a 

 few miles from 'Hobart. He produced some pieces of bone, which he 

 told me he had found in a very " singular cave" on the crown of a 

 steep hill, and into which he had ventured a short distance ; and by 

 the light of a lucifer match, he discovered some fragments of bone 

 partly embedded in the floor of the cave. Thinking that some 

 interest might be attached to them, he had brought them for my 

 examination. From the description which he gave me of the 

 cavern, as well as the character of the fragments of bone, I saw at a 

 glance that the spot was invested with much interest, and accordingly 

 lost no time in visiting it. Accompanied by him as a guide, and a 

 few other friends, we started early one fine winter's morning for a 

 day's exploration, provided with all that was necessary for enjoying 

 a scientific picnic. The day was well advanced before my guide 

 found the entrance to the cave, owing to its very inconspicuous 

 character, and the rough nature of the country making travelling 

 very slow at best. 



I had imagined that I would find it to be a cave by disintegration 

 of carboniferous limestone, which is extensively developed at the 

 base of the hills forming the Mt. Wellington Range But, on the 

 contrary, I found it situated in a greenstone capping of Mt. Fawkner, 

 a hill of about 2000 feet in altitude above sea land. It proved to 

 be very difficult of ascent, owing to the side being covered with 



