255 
2,2 18 ft. 9 pm, for a bore, sunk in the Botanical Gardens reserve to a depth 
of 2,265 ft- 6 in., had not pierced it when boring was discontinued. The 
upper portion, 46 ft. 9 in., of this bore proved sands and clays with Recent 
shells. 
Overlying these limestones at Whaler’s Bluff, on Portland Bav, is a bed. 
about 12 feet thick, of oyster shells and clay, the shells occurring in such 
numbers as to form a mass consisting almosf entirely of shells. This 
oyster bed is regarded by Mr. J. Dennant, F.G.S., F.C.S., in his paper 
Notes on Post-Tertiary Strata in South-Western Victoria, published in the 
Transactions of the Royal Society of Victoria , Vol. XXIII., 1886, as of 
Miocene age. It is not now visible in the cliff to the south of Whaler’s, 
Bluff, but probably once occurred there, and has been entirely removed bv 
denudation before the overlying rbeks were formed. These rocks consist of 
basalt in a decomposed state, which caps Whaler’s, Bluff, extending to the 
south, west and north of this place. They have a thickness at Whaler’s 
Bluff of about 90 feet, but are onhv about 20 feet thick in the cliff near the 
public baths. They also furnish additional evidence of the erosion of the 
Oligocene or Eocene limestones and the Miocene oyster bed, for, in the cliff, 
in two places, there is evidence of two narrow channels, apparently due to 
stream action prior to the outpouring of the volcanic rocks. Here the 
basalt is seen at or near present sea level, with limestone visible on both 
edges for a good many feet, indicating that the volcanic rock, while in a 
fluid state, flowed into' the old streams. 
These volcanics, which are probably of Miocene or Pliocene age, extend 
baek from the coast in a strip several miles wide, bearing in places a thin 
cap of sand. They consist of decomposed and decomposing spheroidal 
basalt, which, strange to say, furnishes a poor, brownish-grey, clayey soil, 
thus affording a strong contrast to the greater number of the basalts of 
Victoria. Along the main Portland-Heywood road, near the junction of 
this and the Port Fairy road, there are beds of volcanic ash and mud, in 
addition to the basalt referred to. These decompose into a dark red soil, 
but of poor quality. 
Basalt also occurs in the cliffs at Cape Grant and outcrops among old 
sand dunes near Mount Chaucer. Capping this, in places is a thin deposit 
of blown sand, while swamp deposits cccur inland in numbers of places. 
From Portland to the south coast at Capes Grant and Nelson, and extend¬ 
ing westward for many miles to the mouth of the Glenelg River, there is a 
cap of dune sandstone (consolidated blown sand of old sand dunes), while 
along the northern margin of Bridgewater Bay and all along that of 
Discovery Bay, Mr. Dennant shows that shifting sand dunes occur. These 
consolidated dunes are probably of Pleistocene age, and! the shifting ones 
are younger, viz., Recent. 
On the northern and north-western shores of Portland Bav there is an 
almost flat expanse of low sand dunes and' swamps, extending back to cliffs 
of the volcanic rocks. Thes.e cliffs represent the old coast-line; the country 
between was once part of Portland Bay, and has been naturally reclaimed 
recently bv the action of waves and wind in filling it up with sand. 
The vegetation in the volcanic area consists of messmate, peppermint, 
native cherry, native willow, prickly mimosa and other acacias, heath, &c., 
which elsewhere in Victoria form the characteristic vegetation of soil of poor 
quality, while that on the older dunes is chiefly stunted sheoak, tea-tree and 
heath, with patches of stunted messmate, peppermint, and manna gum. An 
interesting clump of Eucalvpts, the occurrence of which was kindly brought 
