^0 E. 0. Teale: 



the most extensive occurrence of this age found in Victoria. The 

 extent of the whole belt from its southern border, where it is con- 

 tiguous with the Gippsland plains to the northern limit toward 

 Benalla, i^ about 100 miles, and the greatest width is about forty 

 miles. The general trend of the belt is about N.N.W. It is com- 

 posed in part of sedimentary rocks, consisting chiefly of thick 

 conglomerates, coarse sandstone and chocolate shales and mud- 

 stones, Avith in places interbedded acid and basic lava flows. The 

 sedimentary series in the vicinity of Mansfield contains fossil fish 

 of Lower Carboniferous types, associated with Lepidodendron. 



The strata of the southern portion are very similar lithologically 

 to those of the Mansfield area, but with the exception of an imper- 

 fect fish scale, the only fossils obtained were those of Lepidodendron, 

 found in widiely separated localities in the Macallister valley,, and 

 also that of the Avon. The Geological Survey Map shows this 

 series as Upper Devonian, and the Mansfield region as Carbon- 

 iferous, but the evidence in favour of their separation is incon- 

 clusive, and they are here all regarded tentatively as Lower Carbon- 

 iferous. 



In addition to the above group of rocks, there is a great develop- 

 ment in the northern portion of the belt, and particularly in the 

 Talley of the King River, of acid porpliyritic rocks, which, accord- 

 ing to Professor Skeats (28), appear to be related to the dacites, 

 suggesting their correlation with the dacites of the Strathbogies and 

 -elsewhere, which are generally regarded as of Lower Devonian age. 

 ^llhis is in conformity also with the field evidence of A. E. Kitson 

 (10), who interprets them as being uncomformably overlaid by the 

 Upper Palaeozoic sediments. 



Along the western margin of the Upper Palaeozoic belt is the 

 Earkly Valley, notably on Fullarton's Spur. 0. A. L. Whitelaw 

 shows in his map the occurrence of porpliyritic rocks, some of which 

 Professor Skeats has recognised as altered andesites, distinct from 

 the acid lavas of the Wellington area, and comparable most probably 

 with some of the Lower Devonian volcanics, typically known as the 

 " Snowy River Porphyries." 



Another interesting feature is brought out by a study of the 

 geological map of Victoria, with reference to the eastern and west- 

 ern adjoining formations. On the eastern side the older rocks 

 are Upper Ordovician; no Silurian has yet been recognised. 



To the west, and continuing to the vicinity of the meridian of 

 Melbourne, Silurian rocks, prevail, with only relatively narrow in- 

 liers of Upper Ordovician. 



