138 
THE GEOLOGIST. 
tlicy vary very considerably in different regions, they are best defined by 
the word Permian, which, according to its original definition by himself 
and his associates in Russia, simply means that such rocks lie between the 
upper coal, on which they rest unconformably, and the lowest portion of 
the Trias, by which they are covered. 
It was observed that, in proceeding from north to south (in eastern 
Germany), the Zechstein thins out ; and seeing the vast dimensions which 
the group assumes where true Zechstein is no longer traceable, the author 
suggests that some of the higher members of the Bohemian Kothliegende 
may represent that limestone in time. The term Dyas, recently applied 
to the whole Permian group by Geinitz, is objected to, since it is based on 
the theory that the lower portion of the Permian is exclusively of fresh- 
water origin, as contrasted with the superjacent marine Zechstein, and also 
because the geographical term Permian, involving no theory, had pre- 
viously been widely adopted, and even used by Geinitz himself. 
Sir Roderick having expressed his great obligations to Dr. Geinitz, to 
whose excellent work (' Dyas ') he made many references, and to the name 
of which only he objected, concluded by presenting to the Society a very 
large collection of rock specimens of the Lower Permian of Saxony. 
March 18. — 1. " On the Correlation of the several Subdivisions of the 
Inferior Oolite of the Middle and South of England." By Harvey B. 
Holl, M.D., F.G.S. 
The order of succession of the subdivisions of the Inferior Oolite ob- 
served in passing from the southern side of the Mendips to the typical 
section of that formation at Leckhampton, with the lithological characters 
of the strata, were described in this paper. The classification of the mem- 
bers of the Inferior Oolite employed by Mr. Hull in the Memoirs of the 
Geological Survey, was adopted by the author ; and it was shown that in 
proceeding from Bath northwards, the two upper subdivisions may be seen 
to rise, the building-freestone at the same time becoming thicker, while 
at Aveling the Oolite marl is first seen interposed between the lower 
ragstone and the lower freestone, and at Nailsworth the former is sepa- 
rated from the Oolite marl by the upper freestone, all these beds be- 
coming thicker towards Cheltenham, and thinner in the opposite direction, 
towards Bath. Dr. Holl concluded with some remarks on the strata exhi- 
bited in the Rolling Bank Quarry, and on the geographical distribution in 
England of the members of the Inferior Oolite. 
2. " On the occurrence of large quantities of Drifted Wood in the 
Oxford Clay, near Peterborough." By Henry Porter, M.D., F.G.S. 
The Oxford Clay in the neighbourhood of Peterborough having been 
exposed in clay -pits, the author was enabled to carry on some investiga- 
tions regarding the fossils which there occur in it ; he found the formation 
to be extremely rich in organic remains, and, besides containing many 
species of Ammonites and other Mollusca, which he enumerated, to include 
large quantities of drifted wood, the fragments bearing on their surface 
the impressions of Ammonites. 
3. " On a new Macrurous Crustacean from the Lias of Lyme Eegis." 
By Henry Woodward, Esq., F.Z.S. 
A very perfect specimen of a Crustacean, obtained from the Lias of Lyme 
Regis by Mr. Harrison, of Cliarmouth, was described in this paper as the 
type of a new genus. The nearest living analogues were stated to belong 
to the fossorial group Thalassinidae, from which it differs chiefly in its 
much less rudimentary abdomen, and the length of its chela;. Amongst 
fossil forms, this Crustacean, which was named Scapheus ancylochelis, ap- 
proached most closely to Megacheiriis longimanus, from the Solenhofen 
