116 Transactions of the Royal Society of Victoria. 



veinlets of a second felspar, thus being a microperthite. In 

 one instance I found the felspar intergrown with quartz in 

 the "graphic" manner. Some of the orthoclase felspars 

 are quite fresh, while others aie converted into pinite 

 pseudomorphs, accompanied by the usual large plates of 

 muscovite mica which I have observed in such cases in some 

 of the Ensay rocks. That these pseudomorphs are after 

 potassa felspar is shown by portions remaining centrally in 

 one or two cases still unaltered. A few triclinic felspars 

 occur also in smaller crystals, having small obscuration 

 angles. Some of the crystals of muscovite are probably 

 original, whilst others are certainly secondary, as, for 

 instance, the micaceous aggregates of the pseudomorphs. 



Brown, strongly pleochroic magnesia mica appears also to 

 be one of the earlier-formed minerals, as it is extensively 

 eroded, and has ragged edges, portions of which have, in 

 places, been detached. The same pleochroic halos surround- 

 ing minute crystals, of which I spoke a few pages back, 

 appear here also under the same conditions. Here also such 

 of the minute included crystals which I could examine had 

 a prismatic habit, with rounded edges, and a longitudinal 

 obscuration. Their comparative rarity and their minuteness, 

 so far, have prevented me from isolating any for separate 

 examination, and their real nature must therefore still 

 remain uncertain. This granite mass is about thirty paces 

 across on the line of section, and then the schists continije 

 much broken up, disjointed, and in places decomposed. 



[g) The schists at this place are very massive, and are 

 traversed by small veins of aplite and of quartz. They are 

 jointed, but the bedding is obscure, if not obliterated. In a 

 hand sample the rock is buff-coloured, with a schistose 

 structure, and under the lens it has the appearance of being 

 a rather minute mixture of yellowish-coloured felspar, 

 quartz, and mica. Under the microscope I found this rock 

 to resemble in its structure that described at {e), but it is 

 rather coarser in grain, and with fewer felspars as compared 

 to the quartz grains. The felspars form connected veins of 

 varied width, separating the quartz grains into rude 

 foliations connected with each other. Muscovite mica 

 occurs in crystals among the felspars, and seems to be one of 

 the earlier-formed minerals. There are also a few light- 

 coloured flakes of magnesia mica, and a few greenish prisms 

 of tourmaline complete the composition of this rock. 



