i;i;illSII ASSOCIATION MKKTING. 
311 
reniiiins from St reet, now in I lie ]?ritisli and oilier niuseinns, were eolleetetl 
from this zone, together with the remarkable Pk'.sivsai<rus ineijaccphalas 
(Striteh), of which only two specimens were known, the one contained in the 
IJristol Mnseum, and the other in the Warwick jMnscnm. 
Tile zone of Jwiiioi/i/cs niiff/ila/iix (Sehotli.), which forms so important a sub- 
division of the Lower Lias of France and Belf^-iiim, and contains m these coun- 
ties so rich a fauna, is represented in England by a few eliaracterist ic ammonites 
only, it is ex])osed in the Harbury cutting near AV'arwiek, from whence most of 
2nd. The zone of Aiiiwoinfes Backlandi is well exposed in the Church cliff 
of Lyme Kegis, in the Harburg cutting, in various sections in Somersetshire, 
as at Saltford, and near Eath, and in Gloucestershire and Glamorganshire. 
This zone contains many species of Ammonites, as A. Biicldcoidi, A. roliformis, 
A. Grcenoiifjlii, and A. iurt'dis, and A. Cui/i/heciri, with Lima (jujuntea, and Gry- 
ph/ea arcualii. 
3rd. The zone of Ammonites Tunicri contains many of the Lyme Regis 
saurians, as Ichthyosaurus ptatyodoii, associated with Am. semicostatus (Y. and 
B. ), and A. Bowiiardi, and Peiitacrinus tuhermlatus (Mill). 
4lh. The zone of Aiiniiouites oltusus is best shown at Lyme He^is, between 
Broad Ledge and Cornstone ledges, near Charmoutli. Its beds are very 
fossiliferous ; here are found Am. otAusus, A. stellaris, A. planicosta, and A. 
Dudirssieri. This zone was exposed in Gloucestershire, in the cuttings of the 
Bristol and Binningham railway, and at Bredon, in Worcestershire, a large 
assemblage of its cephalopods was found. 
5th. The zone of Ammonites oxynotus is found near Black Yemi, at Lyme, 
and in the vale of Gloucester, Am. oxynotus, A. lifer, A. lacunatus, lie in this 
zone. 
Cth. The zone of Ammonites raricostatus is well seen at Lyme Begis, in the 
vale of Gloucester, and at Bobin Hood's bay, in Yorkshire. The beds belong- 
ing to this and the preceding zone are very ferruginous, and many of their' 
fossils are preserved with difficulty. 
Ilvppopodium ponderosum, Gryphcea oliliquala, and a thin band of corals 
occupy the upper beds. AVith these are associated many other mollusca and 
Pentacrinus scalaris. Am. armatus, A. dentinodus, and A. varicostatus lie toge- 
ther in the lower beds of the zone. 
ON THE METAMOEPHIC EOCKS OF THE NOETH OF lEELAND. 
On referring to the geological map of Ireland, by Sir Bichard Griffiths, Bart., 
it will be seen that a large area in the north of Ireland is occupied by rocks of 
a mctamorphic nature. These rocks, well exhibited in the county of Donegal, 
arc composed of mica-schists and quartz-rocks, which are seen occupying well- 
marked districts in this part of Ireland. These mica-schists and quartz-rocks 
are subject to great contortions, and have a prevailing south-east dip in the 
north of Ireland. The relative position which these rocks bear to each other 
is well seen in a section of about twenty miles along the coast, between Inish- 
owen head and Mulin head, the extreme north point of Ireland. Althougli the 
miea-sehists and quartz-rocks are several times repeated in this section, the 
result of great flexures and contortions, the section shows that quartz-rocks 
are the oldest rocks of this portion of Ireland, and that they are conformably 
overlaid by the mica-schists. An anticlinal axes occurs among these meta- 
morphic rocks a little south of Mulin head, and on the north side of this axis. 
By Professor Harkness, F.E.S. 
