526 H,. HICKS ON THE PRE-CAMBRIAN 
In the plan of the coast to the south of Nun’s Chapel (fig. 3) the 
Fig. 3.—Plan of Coast south of Nun’s Chapel. 
Nuns Chapel = 
ea2eae2 & 
Sy 
==, = 
= *s 
= OS 
eae & 
<S¥ Chanters Seat 
FS 
a ( 5. Green and purple flags &c. (Plutonia &.). B. Pebidian. 
= | 4. Purple grits and sandstones. A. Dimetian. 
&< 3. Red shales (Lingulella primeva). + Diabase dykes and sheets. 
5 | 2. Greenish sandstones. Xx Intrusive Felstone. 
© | 1. Basal conglomerate. F. Faults. 
manner:in which the Cambrian conglomerates overlap different beds 
of the Pebidian is shown. The conglomerates in the cliff-section: 
(fig. 2) can only be properly examined by boat ; but on the top of the 
cliff, and in the first field to the east, they are well exposed, and may 
be readily explored. Ina westerly direction they occur in well- 
marked detached masses, forming the seaward fringe to the bathing- 
place directly below Nun’s Chapel. Many of the pebbles are of 
large size, and the basal beds can be seen here again creeping over the 
edges of the Pebidian beds. Im the little creek to the S.S.W. of 
Nun’s Chapel the conglomerates are thrown back for a considerable 
distance, as shown on the plan, by a fault; but this fault, again, does 
not prevent the unconformable position of the conglomerates on the 
underlying beds being readily made out at the point to which both 
have been thrown back together. The Pebidian rocks have been 
very freely penetrated by dykes of porphyritic quartz-felsites and of 
diabase in this creek, as also between this point and the creek in 
which the section, fig. 2, occurs. These porphyries were described 
in my former papers, and are also fully referred to by Dr. Geikie. 
The Pebidian beds in this area are mainly porcellanites and breccias, 
chiefly acid breccias, though in the 8.8.W. creek referred to above, 
and in the adjoining one to the east, basic breccias also are found. 
The “‘milk-white flint-like”’ masses, “ adinole,’ described by Dr. 
Geikie at p. 310, and found so plentifully in the breccias, are not, in 
our opinion, concretions or aggregations, the result of metamorphism, 
as claimed by him, but actual fragments of older rocks. These are 
described by Mr. Davies in Notes 17 & 18. 
