T. S. Ilall — GraptoUte Rocks, Victoria, Australia. 439 



11. — The Graptolite-beartng Eooks of Victoria, Australia. 



By T. S. Hall, M.A., Melbourne Uniyeraity. 



(PLATE XXII.) 



Introduction. 



rriHE area occnpieil by Lower Paljeozoic rocks in Victoria is an 

 \_ extensive one, and is pretty equally divided between Ordovician 

 and Silurian, tlie part occupied by Cambrian being small. According 

 to Dr. A. R. C. Selwyn, formerly Director of tbe Geological Survey 

 of the Colony, the total area amounts to somewhere about 30,000 

 square miles in extent,^ and although in this estimate he included 

 all areas occupied by these rocks provided the cover was not more 

 than o50 feet in thickness, it will still leave us with a large extent 

 of country over which graptolites may be found. 



The earliest record of the occurrence of these fossils in Victoria is 

 on a map of Selwyn's published in 1856, where it is stated in a note 

 that graptolites were found for the first time in Australia by C. D. H. 

 Aplin in May, 1856, at a locality indicated on the Saltwater River 

 near Keilor, about ten miles north-west of Melbourne. No identi- 

 fications have ever been made from these beds, which yield a few 

 species of Monograptidee in a poor state of preservation. 



Very shortly after this graptolites were found in the Lower 

 Ordovician rocks of Bendigo. In an essay contributed to tlie 

 Catalogue of the Victorian Exhibition of 1861, Professor McCoy 

 recorded from various localities several species which included 

 Diplograptidee, Dichograptidae, and Dicranograptidas, as well as 

 Monograptus ludensis, which showed that even thus eai-ly almost 

 the whole range of graptolite-bearing rocks had been examined. 



In a similar essay by the same author published in 1867, a few 

 additional forms were noted. 



The first decade of Sir F. McCoy's " Prodromus of the Paleontology 

 of Victoria " appeared in 1874, and contains the earliest figures and 

 descriptions by which we can judge of the accuracy of his previously 

 published determinations. The plates seem to have been printed 

 off several years previously, for Professor James Hall, in liis 

 " Graptolites of the Quebec Group," says that he received a plate 

 from Professor McCoy in 1861, and which from his remarks would 

 appear to be one which was not published till 1875. Two years 

 later, in his fifth decade, Professor McCoy issued figures and descrip- 

 tions of a few more of these fossils. In 1874 Mr. R. Etheridge, jun., 

 published figures and descriptions of several forms which he 

 identified with known species, the date of his paper in the Aunals 

 of Natural History and of McCoy's first decade being almost 

 simultaneous. 



With regard to the determinations contained in these and other- 

 early papers, it may be stated generally that, as was the case of 



^ Intercolonial Exhibition Essays, 1866-7: "Notes on the Physical Geography, 

 Geology, and Mineralogy of Victoria," p. 13. 



