16 Proceedings. 
affinis, Cheirurus Frederici, Dikellocephalus furca, Ampyx pre- 
nuntius, Ogygia scutatrix, Neseuretus ramseyensis, Angelina 
Sedgwickii, ? Olenus impar. 
We note in passing that we have representatives of the 1st 
and 2nd Faunas occurring together. This, we shall find, is still 
more marked in other regions. 
The next district to be described is the important one of 
St, David’s, Pembrokeshire. Little was known about the rocks 
of the St. David’s Promontory until in 1866 Messrs. Salter and 
Hicks drew up a list of the fossils which had up to that time 
been found. Six years later Dr. Hicks gave to the Geological 
Society a full account of the Tremadoc rocks, in which he had 
carefully worked both on the mainland and in Ramsey Island, 
and he compared these beds with those already known in 
North Wales. 
The slates may be seen in the N.E. of Ramsey Island, at 
the N. end of Whitesand Bay, extending inland in a N.E. 
direction, and in Tremanhir five miles east of St. David’s. At 
each place they rest conformably on the Lingula Flags, as we 
have already seen is the case in North Wales. 
In Ramsey Island the lower part consists of grey earthy 
flags of a hard texture, this merges into rock of a bluish-grey 
colour, which is sometimes thick-bedded and tough. Above 
them are dark iron-stained slates of Arenig age. The total 
thickness is about 1000 feet. 
At Whitesand Bay the rocks are very similar. 
At Tremanhir the exposures of the rock are few, as the 
surface of the country is thickly covered with drift, but the 
rock in the few quarries that there are resembles the beds in 
Ramsey Island, with the exception that the middle part is 
more sandy and less cleaved. The Upper Lingula Flags of the 
district consist of hard siliceous sandstones, a shallow-water or 
littoral formation ; these, as we have seen, are followed by the 
tough mudstones of a deeper sea of the Tremadoc period, and 
these again by the fine black muds deposited in the deep Arenig . 
ocean. Dr. Hicks says: “ This intermediate condition” (under 
which the Tremadoc rocks were deposited) ‘‘must have been 
