254 
the summits of all the higher peaks and ranges, as far north 
as Mount Serle, including the singular and picturesque Pound 
Ranges at Wilpena and Warraweena. 2. The hard, fine- 
grained, and micaceous green, grey, and purple slate, sand- 
stone, and flag series. 3. The siliceo-calcareous series, or the 
Angorigina, Appealina, and Oratunga limestones. The dark 
blue, fine-grained arenaceous flags and sandstones of Appeal- 
ina. 
“Second.—The beds that occupy the whole of the country 
south from the above-mentioned line to Cape Jervis, consist- 
ing.chiefly of slates, shales, and sandstones of various tex- 
tures and colours with intercalated bands of gneissose, euritic, 
and micaceous schists, bands of quartz rock, and crystalline 
limestone, associated in certain localities, from the Gawler 
River south to Cape Jervis and Port Elliot, with eruptive 
granitic and hornblendic rocks. 
“Third.—A series of beds, certainly the lowest in geologi- 
cal position in the whole of the central chain, but occupying 
a comparatively small area, chiefly confined to the watershed 
of the Onkaparinga. On these the only profitable goldfield 
hitherto discovered in South Australia is situated, and it is, 
I think, along the axis of these lower beds only that any im- 
portant extension of the already known auriferous area can 
be expected." * 
Selwyn was in error by referring his three main divisions 
to different geological ages, and as being unconformable with 
each other; and, at times, errs in fixing the geological hori- 
zon of the beds that he describes, but the order of succession 
laid down by this experienced field geologist is the correct 
one. He clearly shows ihat the purple slates, with their 
associated quartzites and caleareous beds, occupy the highest 
position in the series, and that the beds have a descending 
order as they outcrop to the eastward. With great discern- 
ment he forecasts the possibility of an error in his conclusions, 
and says: — “It is just possible that no such natural divisions 
exist in the rocks of the South Australian chain as are here 
sketched out, and that the difference in general mineral and 
lithological charaeters, observed between the northern and 
southern rocks, is entirely due to the metamorphic influence 
of the granitic axis that, at Cape Jervis, extends in a north- 
easterly direction, showing itself at intervals on the surface 
to Angaston, and then seems to break through the chain and 
continue its course to the north-east, passing under the great 
tertiary flats of the Murray basin; and, in all probability, 
again re-appearing in the Barrier or Stanley Ranges.” f 
* “Geological Notes.” by A. Е. C. Selwyn. Parl. Paper (No. 
20), 1860, p. 14. 
t Op. cit., p. 14. 
