30 THE VICTORIAN NATURALIST. [Vol. XXIV, 



with in the Macallister valley, above Glenmaggie, till Mickey's 

 Creek is reached. 



The result of this broad anticlinal structure on the rock ex- 

 posures is well seen by reference to the outcrops of the igneous 

 rocks. Two well-defined parallel bands of these rocks can be 

 traced almost continuously along the face of the opposing scarps 

 for a great distance. They form parts of the same lava sheets 

 which are interbedded with the sedimentary series, were folded 

 with them, and have since been separated into these two distinct 

 lines of outcrop by denudation. Both belts of these rocks, as 

 indicated on Murray's map, can be extended considerably to the 

 north. And at Observation Point they appear to widen and 

 unite on the crown of the less dissected part of the fold. The 

 igneous rocks of the series appear to be invariably found at or 

 near tlie base of the series. This has been shown in numerous 

 sections given by Murray, and is confirmed by the examination 

 of many additional sections by the writer. In places they rest 

 directly on the upturned edge of the Lower Palaeozoic, while at 

 others intervening sedimentary beds, chiefly coarse conglomerates, 

 are found. The greatest observed thickness of these rhyolitic 

 lavas is to be found along the eastern side of tlie anticlinal axis at 

 Wellington, where, as previously noted, it rises to about 2,000 

 feet. The western counterpart of the WeiHngton rocks is pro- 

 bably to be found in a section to tlie south-west of the Dolodrook 

 junction. Here the range of thickness is under 1,000 feet, and 

 intervening thin sedimentary beds lessen the actual thickness of 

 the lava flows to some extent. Some of these rocks are hard, 

 durable, and attractive, and would certainly be valued as orna- 

 mental building stones if they were in a more accessible position. 

 The soil and vegetation on these areas is generally superior to 

 that of the sedmientary rocks, but is still only of fair quality. 

 Many of the steeper spurs, however, where the rocks outcrop, are 

 extremely rough and rugged, and yet there are very few places 

 where one cannot find evidence of cattle, which have sought out 

 the occasional grassy slopes between the rugged knolls. The 

 question of the correlation of the Wellington volcanic rocks with 

 those of the Snowy River series calls for consideration. The age 

 of the latter has been fixed as Lower Devonian, but the age of the 

 Wellington series appears to represent a slightly later phase of 

 this great volcanic activity. The greatest development of the 

 volcanic rocks is at the base of the Wellington series, but it does 

 not appear possible to separate them from the overlying sedi- 

 mentary rocks. No break can be noted, and these rocks appear 

 to make one continuous group. The scraps of fossil evidence 

 obtained here and there would indicate that the uppermost beds 

 of the series all represent the Avon series, and are therefore 

 Lower Carboniferous. 



