SCIENTIFIC SUMMARY. 
275 
traced through this range, the latter seldom showing any well-marked Ptero- 
cerian division, and the former being most connected with the overlying 
series. Above these are limestones hitherto called ‘ Portlandian,’ in which 
two zones are constant ; hut above all are vacuolar Oolites, which alone may 
be truly correlated with the Portland rocks of England. The whole of the 
beds in this range are eminently calcareous, a true clay being scarcely any- 
where seen. 
2. The Charent.es. — In these two Departments the lower portion is very 
calcareous, and the distinction of one part from another very slight ; but the 
highest portion, both near Cognac and on the He d’Oleron, yields beds which 
may be paralleled with our true English Portland rocks. 
3. Normandy. — The complete sequence has here been made out, from the 
true Oxford Clay of Dives to the Virgulian of Havre, and the similarity of 
the whole to the sequence in Dorsetshire is very remarkable. ‘ The Trou- 
ville Oolite ’ is the exact representative of the ‘ Osmington Oolite ’ with the 
Nothe Grits below ; but the place of the Sandsfoot clay is taken by the true 
Coral Pag, whose right position in the Weymouth section is hereby deter- 
mined. The Supracoralline beds are the sands of Glos, and the Astartian 
beds are the Trigonia-be&s of Havre, which are the exact representatives of 
the 1 Kimmeridge passage-beds.’ 
4. The Pays de Bray. — Nothing below the Virgulian is here seen, and the 
commencement of the so-called 1 Portland beds ’ was considered by the 
author to be at a lower level than it is placed by M. de Lapparent, on account 
of the similarity to beds at Boulogne. The true Portland rocks occur as 
ferruginous sandstones with Trigonia gibbosa. 
5. Boulonnais. — The Houllef ort limestone was correlated with the 
Osmington Oolite. The Coral Bag of Brucdale was considered equivalent 
to that of the Mont des Boucards, the so-called limestones of the latter place 
being Supracoralline. The Nerinean Oolite and the Gres de Wirvigne 
represent the Astartian. The higher parts of the series have been already 
correlated. 
From this study it was proposed — that the ‘ Lower Calcareous Grit,’ and 
almost all the Coralline Oolite, should be placed in the Oxfordian series as 
the upper division, under the name ‘ Oxford Grit ’ and 1 Oxford Ojlite ; ’ that 
the Corallian consists of two parts, the Coral Bag and the Supracoralline 
beds ; that the Kimmeridgian should include the Astartian and Virgulian, 
the Pterocerian being a subzone ; that the ‘ Upper Kimmeridge ’ and the 
Hartwell clay, with the ‘ Portland sand,’ should make a new subdivision to 
be called Bolonian (the northern and southern types being both represented 
at Boulogne), which may be divided into Upper and Lower; that the true 
Portland limestone and the Purbeck be united into one group, as Lower 
and Upper Portlandian ; the fact of the latter being freshwater being paral- 
leled by parts of the true Portland having that character. 
Changes of Level in Lancashire. — In a paper on the date of the last 
change of level in Lancashire, read before the Geological Society on the 
6th April by Mr. T. Mellard Beade, the author described some observations 
made by him at Blundellsands, on the coast of Lancashire, near Liverpool, 
according to which, judging from the position of high-water mark, the land 
had gained considerably upon the sea between 1866 and 1874. At one end 
