IGNEOUS ROCKS OF SOUTH-WESTERN VICTORIA. 395 



but some of the columnai'-shaped ones are beautifully clear and 

 pellucid. Many of these remain almost black, even in a thin sec- 

 tion ; at the edge, where this is thinnest, they become of a faint- 

 green color. There are also magnetite grains, and perhaps a little 

 decomposed olivine. 



Behind Mount Koroite, on a hill close to the railway line, a rock 

 is quarried which looks to the eye like a basalt. It is compact, 

 and, though fissile, is less so than the Carapook and Brit Brit rocks. 

 Its specific gravity is 2-87. There is much felsjjar, some of which 

 is apparently sanidine, and, in addition to other minor ingredients, 

 it contains olivine in good-sized crystals. 



At Phoines, what looks like the same rock (judging from its 

 microscopic structure) has, amongst other varieties, been used in 

 building the station villa. From a heap of stones left over by the 

 masons I noticed two or three varieties of rock, and thought at first 

 that they must have cojne from different localities. The proprietor, 

 Mr. J. R. McPherson, however, assured me that all were quarried 

 in the paddocks close to the house. 



An interesting discovery was made at the Mount Koroite outcrop. 

 Almost at the top of the hill a shallow excavation of a few yards 

 in diameter has disclosed a whitish felsi)athic tufa, small blocks o£ 

 which now lie in the hollow. On breaking one of these blocks in 

 two for convenience of transport, impressions of cycads were seen 

 on both the fractured surfaces. Mr. Robert Ktheridge, of Sydney, 

 who has kindly examined some of the impressions for me, states, 

 " that very little doubt can exist that the plant is a Mesozoic cycad, 

 called Otozamites. It also occurs in the Queensland beds of a like 

 age." It should be mentioned that the sedimentary strata, amongst 

 which these igneous rocks appear, are of acknowledged Mesozuic- 

 age. 



Rocks of a still more basic character than that at Mount Koroite 

 are also intermingled with the rest in the neighborhood of 

 Coleraine. On the road to the Giant Rock two steeply inclined 

 conical hills, locally known as Adam and Eve, stand close together, 

 and form conspicuous objects in the landscape. They consist o£ 

 lava, which must have been so viscid when in a molten state that 

 it congealed at once, there being no sign of any flow from either 

 hill. From the blocks of stone I have picked out small fragments 

 of olivine, and in thin sections this mineral appears to be the 

 principal ingredient. The rock is black, and so dense that I have 

 not succeeded in making any section really transparent. Its 

 specific gravity reaches 3. A quarry has been opened at the foot 

 of the lower of the two hills, which, though no distinction is made 

 by residents, I call Eve, but the stone is now almost white, and so- 

 much decomposed that no clue is afforded as to its original 

 composition. Conical hills are tolerably numerous around Cole- 

 raine, but the others are smooth and clothed with grass, while 

 these two are rugged and almost devoid of vegetation. Allied to 



