neighbour.  Like the mountains in the east Mount Arapiles consists of sandstone passing into quartz, the whole apparently an altered sandstone, the structure being in one part almost destroyed, in others perfectly distinct and containing pebbles of quartz.  At the western extremity this rock occurs in columns, resembling, at a distance, those of basalt. (See Plate 31.) On the steep slopes grew pines, casuarinae, and a variety of shrubs among which we found a new species of Baeckea, forming a handsome evergreen bush, the ends of whose graceful branches were closely covered with small white delicate flowers.* This mass occupies about two square miles, its highest summit being elevated above Mitre Lake 726 feet.  I ascended this hill on the anniversary of the battle of Salamanca and hence the name.

(Footnote.  B. calycina, Lindley manuscripts; glaberrima, foliis planis sparse punctatis oblongo-cuneatis acutis, floribus pedicellatis terminali-axillaribus, laciniis calycinis petaloideis petalis longioribus.  Near B. virgata.)

MR. STAPYLTON’S EXCURSION NORTHWARD.

July 24.

While Mr. Stapylton rode northward in search of the Wimmera I proceeded to examine and survey some of these remarkable lakes.

SALT LAKES.

On the margin of one of them, bearing 55 1/2 degrees West of North from our camp, a green hill of rather singular shape rose to a considerable height above the surrounding country.  I found the water in the lake beside it shallow and quite salt.  The basin was nearly circular though partially filled with firm level earth which was water-worn at the brink, its surface being about three feet higher than the water.  This was surrounded by a narrow beach of soft white mud or clay in which we found no change on digging to the depth of several feet.

GREEN HILL LAKE.

The green hill was the highest of several semicircular ridges whose forms may perhaps be better understood by the accompanying plan.* There was a remarkable analogy in the form and position of all these hills; the form being usually that of a curve, concentric with the lake, and the position invariably on the eastern or north-eastern shores, a peculiarity I had previously observed not only in the lakes near the banks of the Murray but also in others on the Murrumbidgee and Lachlan where the ridge consisted of red sand.  The country on the western shore of these lakes is, on the contrary, low and wooded like the surrounding country.  In such hills concretions of indurated marl frequently occur, but the earth they consist of is sometimes light-coloured, in other cases very dark, like the soil from trap-rock, and the ridges beside the lakes on the Murrumbidgee, consisted of red sand.

(Footnote.  Having modelled this feature I have the satisfaction of presenting to the reader the first specimen of a plan of ground worked from a model by the anaglyptograph, an important invention recently perfected in this country by Mr. Bates and likely to be of very considerable value in the representation of the earth’s surface under the skilful management of Mr. Freebairn.)