in his valuable paper on the Devonian rocks o£ North Gipps- 

 land, viz., that " the great masses of quartz porphyries" (such 

 as those I have described, p. 2) " are the denuded stumps of 

 the volcanoes, around which accumulations of felstone ash and 

 agglomerate, with felsitic rocks of indefinite character are 

 seen to be grouped."* In other words, they are the last 

 traces, though obscure as to their original characters by 

 metamorphism, of the once trachytic ash and agglomerates 

 of L'pper Palsezoic volcanoes. 



Crossing the spur dividing Stony Creek and Limestone 

 Creek, the porphyries are seen to be penetrated by strings 

 and veins of quartz, and in some places to assume an almost 

 vesicular appearance. At lower levels towards Limestone 

 Creek, the sedimentary rocks again appear, consisting of finely- 

 laminated slates, sandstones, and interbedded bands of whitish 

 marble or dense -blue limestone, dipping W. at 70°. The 

 marble bands are from 10 to 250 feet thick, more saccharoidal 

 than the Stony Creek deposits, but full of seams of limonite, 

 parallel to the bedding planes, and much jointed ; they are 

 also perforated by numerous caves. On the grassy sub-alpine 

 fiats of Limestone Creek are deposits of auriferous Tertiary 

 gravels from 5 to 12 feet deep. Ascending the steep spurs to 

 the west, the slates become more corrugated and micaceous. 

 On the upland flats, near the crest of the range, masses of 

 diorite are seen ; the rich carpeting of grasses proving the 

 fertility of the soil decomposed from these potash-yielding 

 rocks. These intrusive masses are probably connected with 

 the periods of PalcTozoic volcanic activity, as the rocks at con- 

 tact are indurated and otherwise altered. As the crest of the 

 range is reached, the slates become very much corrugated, 

 micaceous, and full of quartz veins ; further to the north, 

 along the line of these semi-altered slates, A^eins of micaceous 

 iron-ore are plentiful in a quartz matrix. On the crests of the 

 range the rocks assume a vertical dip and decidedly meta- 

 morphic character as gneissose schists ; while in descending 

 towards Marengo Creek masses of granite are seen standing 

 out in huge tors. This is probably a metamorphic granite, and 

 is continuous across the valley of the Marengo Creek to Mount 

 Leinster, which is a bold rounded peak on the Dividing Range. 

 At the summit of this mountain the granite gives place to 

 quartz-porphyry of an intrusive character, which has ap- 

 parently been exposed by sub-aerial denudation. 



On the west side the metamorphic schists are constituted of 

 argillaceous, argillaceo-micaceous, and areno-argillaceous 

 materials dipping frooi vertical to 85° to W. On the slopes 



* " Devonian Eocks of Gippsland ;" p. 200. 



