108 Transactions of the Royal Society of Victm^ia. 



in the micaceous foliations, and are generally broken across. 

 The principal difference between this rock and the last one 

 described is in the scarcity comparatively of magnesia mica, 

 and in the laige amount of quartz in grains of various 

 sizes. 



The subjoined analysis was kindly made for me in the 

 laboratory of the Technological Museum, by Mr. Jas. C. 

 Fraser : — 



Analysis No 4. — Quartzose Mica Schist.* 

 Si.O. ... ... ... 72^60 



AI.2O3 .. 







9-03 



Fe.A .. 







10-00 



Fe.O 







105 



Ca.O 







•50 



Mg.O 







312 



K2O 







2-44 



NagO 







2-62 



H2O 







•50 





]0r86 



I selected a third sample from a quartzose bed adjoining 

 a dyke at c, Fig. 2, Plate 1. It is composed of rather large 

 rounded to angular grains of quartz, full of inclusions, and 

 with fluid cavities without bubbles. The inclusions are 

 mostly minute rounded flakes of dark brown mica, such as 

 I have frequently observed in quartzose hornfels at Swift's 

 Creek and in other parts of North Gippsland. Besides the 

 quartz there are flakes of muscovite in less amount than the 

 numerous small, greenish-coloured prisms of tourmaline. 

 In order to complete the comparison of varieties of these 

 schist beds, I selected a fourth example, being one taken 

 from close to the contact at the place marked (e) in the 

 diagram section, Fig. 2, Plate I. This sample is strongly 

 nodular, but otherwise much resembles in appearance the 

 second example at (a.) Judging from the example of a thin 

 slice, this rock is composed of quartz in angular grains, 

 scattered through a ground mass of muscovite mica. Fluid 

 inclusions are common in the grains of quartz, which differ 

 much in size. Tourmaline crystals of minute size are also 

 numerous, arranged parallel to the foliations. Most of these 

 crystals have, as in other samples, been broken across the 



* I found tlie specific gravity of a sample of this rock to be 2*723. 



