Reviews—Stanford’s Geography—Australian Geology. 427 
water of the Flowing Wells. The Upper Cretaceous series consists 
of sandstones, quartzites, ete. (containing G@lossopteris?), which are 
continuous with beds of Desert Sandstone. This peculiar formation, 
which probably has only one-twentieth of its former extent, is 
partly marine, partly terrestrial, and has undergone much silici- 
fication. The Cainozoic system is mainly represented by volcanic 
rocks, which began to flow early in Tertiary times. The most 
interesting of the higher deposits of this age are some breccias, rich 
in the bones of extinct marsupials and birds, associated with fresh- 
water mollusca, such as Delania, Limnea, Physa, etc.; also teeth 
of Ceratodus. 
Victoria.— Although this is the smallest of the states or colonies 
of the mainland of Australia, its geology is more complex than that 
of any other. The dominant fact in its geological structure is that 
it consists of a base of Lower Paleozoic and Archean rocks which 
have been thrown into a series of folds along two lines nearly at 
right angles to each other. The oldest rocks are Archean, and 
the Lower Palzozoics are well represented, especially in the case 
of Ordovician sediments, which possess a peculiar interest from the 
circumstance that auriferous reefs, such as those at Bendigo and 
Ballarat, are connected with this formation. Bendigo is situated 
on a northern spur of the Victorian highlands, and Ballarat on a 
southern spur of this mountain complex. 
Gold-mining in Victoria is by far too large a subject for the present 
review, seeing that it has yielded something like £250,000,000 in 
the course of its history. There is, however, an interesting notice 
(Science Progress, July, 1906) by Professor Gregory, which bears on 
the most modern aspect of mining in this country: ‘‘ Years ago 
Bendigo was described as exhausted, but the mining industry is still 
flourishing there. It shows the deepest gold-mining in the world. 
It was at first famous for its ‘allaneial oravels, and then 
for the exceptional richness of its ‘blows’ of quartz, which stood up 
im crags, owing to the wearing away of the softer slates. The quartz 
“lows? seen on the surface were soon crushed, and the miners 
followed them underground. This work led to the disappointing 
discovery that the quartz-veins, instead of continuing to unknown 
depths, became thinner, and soon pinched out.” Ultimately it was 
discovered that these wedge-like reefs were found to be the lower sides 
of arches of vein-quartz, which were connected with arch-like foldings 
in the country rocks; hence the lodes were ee ‘saddle reefs.’ It 
is to the systematic exploitation of these ‘saddle reefs,’ so well 
described by Professor Gregory, that the create success of gold- 
mining at Bendigo is due. He then proceeds to speak of Castle- 
maine, where the surface-gravels were phenomenally rich, whereas 
the quartz-lodes have been poor. He suggests that here the gold- 
mines are close to intrusive granitic rocks, causing much secondary 
concentration. This material has been removed by denudation, 
forming the rich alluvial deposits, and only the roots of the gold 
shoots remain. 
Victorian geology presents many other points of interest; and the 
Carboniferous system, though not rich in workable coal, possesses its 
