114 TRANSACTIONS OF THE PLYMOUTH INSTITUTION. 
constitution to Professor Bonney's "granulitic group," could be 
seen cutting the serpentine — the granitic bands often weathering 
red, and the basic bands being more or less porphyritic. A more 
extensive exposure of the same rock was to be seen still further 
east, below Holestrow, north of Pentreath Beach. On the west 
side of Lizard Head a banded granulitic rock, of yellowish-white 
colour, traversed the dark schistose cliff in a winding manner, 
resembling a serpent 100 yards long, with its head at the water's 
edge, and its tail near the top of the cliff. "When the light shone 
favourably the resemblance extended to the scales on the head, 
and even to the well-marked eyes. 
The gneissic outlying rocks, with their porphyritic basic dykes, 
were next described. Mr. Teall considered these rocks analogous 
to those of the Scourie dyke region in Sutherlandshire. The 
coarser gneisses were found most to seaward, and the rocks 
became finer and more granulitic as they approached the mainland. 
Many appeared to be transitional between typical gneisses and 
granulites, and the micaceous, actinolitic, and hornblendic schists of 
the mainland. 
Proceeding east, several exposures of micaceous schist were 
seen on both sides of Penolver Head, and the west side of 
Bass Point. These could be best examined in the small cove 
between these points. This cove was called Trecrobin on the 
1-inch ordnance map, Polledan on the 25-inch parish map, and 
was locally known as Belidden. The cove was due to the 
disintegration of the rock, consequent on a fault which caused 
the rocks on the west side to dip south of west, whilst those 
on the east side, in conformity with the general divisional planes 
of the district, dipped north of east. Penolver Head was marked 
by a broad band of epidote, conspicuous, when seen from a boat, 
by its light green colour. Both Penolver and Bass Points were 
composed of dark hornblende beautifully banded with epidote and 
felspar, and the former showed porphyritic crystals in some of the 
hornblendic bands. 
Pen Vose, or Parn Voose, north of Church Cove, had been 
fully described by Professor Bonney and Mr. Teall. It was 
within ten minutes' walk of Landewednack Church, and should 
be visited by everyone interested in geology. Fine and coarse, 
massive and schistose gabbros, porphyritic diorites, serpentine and 
banded crystalline rocks, with a granitic vein, were there found 
