116 Proceedings of the Royal Society of Victoria. 



zoic rock. Near the Stud Road the rock is very much broken, 

 and the beddin^ is indistinguishable, but the rock is not otherwise 

 altered. The next cutting is about two miles to the east of the 

 Stud Road, where the Lysterfield Road crosses the foot of a hill ; 

 the rock shown has lost all sign of sti^atification, is harder than 

 the unaltered rock, and is coloured red with iron. At the sum- 

 mit of the hill small pieces of indurated I'ock are scattered about, 

 some of them showing traces of stratification. A series of hills 

 of similar formation lies to the south-west of this hill, towards 

 the Lower Reservoir. In a quarry for road-making, near the 

 foot of one of the hills, the altered rock is very hard, and has 

 no apparent stratification. In one part of the face of the quarry 

 there is some very decomposed rock, containing a good deal of 

 mica- it underlies the altered I'ock, and may be a granitic dyke. 

 The surface of some of the altered rock is encrusted with 

 secondary mica. 



To tlie east and south-east of these hills there is a great 

 number of smaller hills showing granite bosses near their sum- 

 mits, but I could find no other rock except at two places ; tlie 

 first is about half-a-mile south of the Lysterfield Road, and is 

 marked (12) on the sketch map. At this point, near the foot of 

 a hill, there is an outcrop of intensely altered stratified rock, 

 containing white mica, and bedded vertically ; it has a strike 

 N.N.E., or at right angles to the slope of the hill. The outcrop 

 of granite begins about ten yards higher up the hill, but the 

 actual contact is hidden by soil. The second place where other 

 rock besides granite is exposed is marked (11) on the sketch map. 

 A hill, showing large outcrops of granite, is crossed by a dyke 

 about six feet wide, and exposed for about 100 yards ; the 

 granite can be seen on both sides, but the line of contact is 

 hidden by soil. In structure the dyke rock is much finer grained 

 than the granite, and was therefore probably formed under a 

 smaller pressure and later than the granite. Further south, on 

 Bald Hill, loose pieces of rock, similar in appearance to that in 

 the dyke, are found above the granite in a cutting, but no dyke 

 can be seen. 



