265 
In the type district these beds can be studied to advan- 
tage in the Tapley's Hill quarries; aloag the spur, which 
connects Tapley's Hill with the coast at Marino; in the bed 
of the Onkaparinga, where they have been crushed into 
short, wavy contortions; and in other outcrops. North of 
Adelaide they are of frequent occurrence, intercalated with 
other members of the series. On the west side of Mount Re. 
markable they are thrown down to the face of the great 
Spring Creek fault; and in the Horrocks Pass, near Wil- 
mington, they make a very imposing feature, capped towards 
the sea by an escarpment of limestone, which, as the next 
in ascending order, can be referred to the Brighton series, 
the whole face being probably a thousand feet in height. 
In some parts of the north the beds have not developed 
cleavage, but split readily in lamine parallel to the bedding, 
producing thin flagstones. This is the case in their occur- 
rence on the western side of Mount Remarkable, in a positioa 
where their determination, as belonging to the Tapley’s Hill 
horizon, is placed heyond all doubt. In places, both north 
and south, the beds have become much decomposed and con- 
verted into a kaolinised rock. 
To further elucidate the stratigraphical features of the 
beds in question, two sections, in the type district, will now 
be described in some detail. 
III. THE FIELD RIVER SECTION. 
The small stream, which has received the dignified name of 
“river,” takes its rise near the Happy Valley Reservoir. The 
stream crosses the Main South Road one mile north of Reynella, 
from which point it follows a meandering course of four and 
a half miles, and finds its outlet to the sea at Haliett's Cove. 
The line of section shown in the diagram (Plate xliii., fig. 1) is 
about three and a half miles in length, and in a direction a 
little north of east and south of west. In the upper part of 
the stream the section has been taken from the outcrop 
Shown on the north bank, and in the last mile from the south 
bank. The general strike of the beds is north and south, 
with a prevailing dip to the west. The beds, however, roll 
considerably along the line of strike, in consequence of 
Which there is frequently an apparent dip to the south. 
.As already intimated, there is no defined line of distinc- 
tion between the Tapley's Hill slates and the calcareous 
series which immediately overlies them. The passage is 
Indicated by a gradual increase of carbonate of lime in the 
stone. Тһе bridge over the Field River, on the South Road, 
May be conveniently taken as the line of demarcation. On 
the west side of the bridge the stone is a calcareous, banded 
