27 



ON THE POSITION OF THE GORDON LIME- STONES, . 



EELATIYELY TO OTHER PALEOZOIC 



FORMATIONS, &c. 



By C. GOULD, F.G.S., Government Geologist. 



Several years ago a collection of remarkable fossils was made ■ 

 by Dr. Milligan, and subsequently lodged in the Society's 

 Museum. They were entirely, or in most part, obtained at 

 the Grordon river in Macquarie Harbor. 



These fossils occur in lime-stone, but a glance is sufficient 

 to show their distinctness from those which are so abundantly 

 contained in the ordinary lime- stones of the colony, as at 

 Mount Wellington, Fingal, &c., &c. 



This collection has been supplemented by one made by 

 myself in the summer of 1862, which I had the pleasure of 

 submitting to the Society on my return, pointing out at the 

 time their lower silurian aspect, and enumerating a few of the 

 principal forms. 



I have now further to add that, taking the opportunity 

 afforded by a recent visit to Melbourne, I made a selection of 

 the most typical specimens, and submitted it to the judgment 

 of Professor M'Coy, the most competent Palaeontologist in the 

 colonies. He immediately identified several of the specific 

 and most of the generic forms, and although from want of 

 access to my notes I am unable on the present occasion to 

 forward a list of the species so determined, it will be sufficient 

 for my purpose to state broadly the results of his examination, 

 which I may point out are confirmatory of my originally 

 expressed views. 



It appears that these lime-stones are contemporaneous with 

 the beds at the very base of tlie lower silurian system of - 

 Europe and America, anterior to the described fossilferaus 

 beds of Victoria, as well as to the Calymene containing beds 

 of the Eldon Valley in this country. 



The fossils principally belong to the family of the Ortlio- 

 oeratidce, together with Corals, Murchisonice, and species of 

 Haphistoma. The absence of Trilobites and Graptolites is 

 not-ceabl'e, the more especially as sand-st3ne beds, inti-- 

 mately associated with the probable equivalents of these lime- 

 stones cropping at the Mersey, contain one, or perhaps two, 

 species of Trilobite clearly allied to the older forms described . 

 by Barrande and American authors. 



The extensive series of metamorphosed rocks forming the - 

 larger portion of Western Tasmania are inferior to this lime- 

 stone, and, I may take this opportunity of remarking, the 

 absence of gold in paying quantities in the districts hitherto 

 examined may be attributable to this reason. 



