60 Personal Observations in the 
The chemical constitution of the latter is aluminum 35, 
silica 48, and water 13; it is found in cavities twenty or 
twenty-five feet in diameter; and could be profitably turned 
‘to account in the manufacture of china glass. The smoky 
quartz is of great beauty, and besides being an ornament to 
museums, is valuable as an article of trade for jewellers’ pur- 
poses. Hence it would be a profitable investment for the 
employment of labour; many valuable specimens could in a 
short time be procured by three or four workmen under good 
superintendence, and the principal expended (£200 would 
cover all) would be profitably returned by the sale of speci- 
mens. : 
The black tourmaline or schérl is interesting on account of 
the peculiar form in which it is crystallised. While on these 
ranges, as well as on other occasions, the absence of mountain 
limestone and mica slate in our primitive rocks struck me as 
a very remarkable fact, in some measure accounting for the 
scarcity of precious stones in our plutonic rocks. 
III. Fish.—In the spring months the Goulburn is too deep 
to afford a plentiful supply of fish, but later in the season 
they may be obtained in large quantities. As soon as the 
volume of the rivers begins to diminish, the finny inhabitants 
leave the mud at the bottom, where they had concealed them- 
selves for warmth, and disport themselves in the higher tem- 
perature on the surface of the water. Seven different species 
of fish are known by me to exist in the Murray; and five 
other distinct species inhabit our smaller rivers. 
Of Mollusca only four species haye as yet been found in 
the rivers and lakes of Victoria, viz., three varieties of uni- 
valve, and one of bivalve. It is difficult to account for this 
remarkable and somewhat characteristic fact; but I am in- 
clined to think that the absence of limestone in our moun- 
tains and the long summer droughts stand in some connection 
with it. The Mollusca referred to are— : 
1.—Lymnaea palustris (?) of Lamarck. This shell is about 
one inch in length, and consists of three or four rapidly 
decreasing volutions, from left to right. It is diffused through 
"all our lagoons. 
2.—Lymnaea peregra (?) of Lamarck. The shell of this spe- 
cies is about three-eighths of an inch in length; the volute 
winds from left to right, and the colour is a dark grey. It is 
very plentiful in the low plains, which in winter are covered 
with water, but become dried up in the warm season. 
