Reviews — The Geological Survey of Victoria, 219 



while tlie most important of those common to Victoria and Canada 

 are Diplograpsus pristis, D. miicronatus, D. rectangular is, Phyllograptus 

 typus, Didymograpsus caduceus, Graptolites Logani, and many others. 

 This community of fossils is, however, not confined to the Grapto- 

 lites, but extends to other classes of animals, such well-known species 

 as, for instance, Orthoceras hnllatum and Phacops longicaudatus, occur- 

 ring in the Upper Silurian rocks of Victoria. 



Notwithstanding the occurrence of these fossils, the geological 

 -surveyors have not attempted, and we think wisely, to correlate the 

 Victorian deposits with those of other regions more closely than is 

 ■indicated by the terms Upper and Lower Silurian. 



The Silurian rocks have been stated by .Mr. Selwyn to be, so far 

 as we know, "the source whence the whole of the gold now pro- 

 diiced in Victoria has originally been derived." An inspection of 

 Mr. Selwyn's map will show how large an extent of surface they 

 now occupy, while the arrows indicating the dip reveal a con- 

 siderable amount of undulation. It is therefore certain that a very 

 large area of the same portion of the series has been subjected to 

 denuding influences, and if that portion be the one containing the 

 gold-veins,^ or if the gold-veins occur throughout, as they appear to 

 do, the hugeness of the great model -pyramid exhibited in the Inter- 

 national Exhibition of 1862 will no longer surprise us, especially 

 when we recollect that gold still occurs in situ over a considerable 

 portion, if not the whole, of this area, and the auriferous drifts also 

 occupy a great extent of country, and are even richer in the precious 

 metal than the rocks whence they were derived. 



The Devonian formation appears to be altogether absent from the 

 colony, but the Carboniferous period is considered by Prof. McCoy 

 to be represented by the formation which is mapped by Mr. Selwyn 

 as Upper Palaeozoic, and which has yielded species of PMllipsia, 

 Brachjmetopus, and Bairdia, with Productus, Lepidodendron, etc. — 

 the first-named genera being characteristic of the Carbonilerous for- 

 mation in Europe. 



These Upper Paleeozoic deposits do not appear to possess any 

 wide geographical range in Victoria, nor to yield minerals of econo- 

 mic value, although in certain localities they afford freestones suitable 

 for building. In the "Victorian Essays " Mr. Selwyn stated that in 

 several localities thick masses of conglomerate occur towards the 

 base of the series ; this conglomerate is composed of rounded pebbles, 

 with occasionally angular fragments of all sizes, — of granite, green- 

 stone, various porphyries, hard slate, gritty sandstone, grey quartz - 

 rock, and quartz ; and he remarked that the character of the beds is 

 " suggestive of the results likely to be produced by marine glacial 

 transport." 



Eegarding the Secondary rocks there has always been some con- 

 siderable difference of opinion, the New South Wales geologists con- 

 tending that their coal-formation is of Palaeozoic age, notwithstanding 

 the Oolitic-looking plants contained in it, while Professor McCoy says 



1 The gold-veins appear to run pretty constantly nearly IS", and S. 



