PROCEEDINGS OF GEOLOGICAL SOCIETIES 



137 



Dr. Buckland from stratigraphical considerations, and the subsequent modi- 

 fications and further subdivision established by recent careful comparisons 

 of the fossils having been briefly noticed, the author proceeded to define 

 the two portions of the Lias which were treated of in this paper. The 

 Middle Lias was stated to comprise all the beds between the zone of 

 Ammonites communis above, and that of A. raricostatus below ; and the 

 Upper Lias to include the beds commencing with the zone of A. cum men is, 

 and ending with that of A. Jurensis ; or, all those resting on the zone of 

 A. spinatus, and superposed by that of A. JfurcJo'sonice, — the beds formerly 

 termed ' the Sands of the Inferior Oolite ' being referred to the L~pper 

 Lias. The sections exposed at Black Venn, Westhay Cliff, Golden Cap, 

 and Down Cliffs were described in succession, the fossils found in each bed 

 being given, as well as the vertical range of the Ammonites. 



The occurrence of a new genus of the Belemnitida? in the Belemnite-beds 

 of the Middle Lias was noticed, and a description of its general features 

 given, with a list of the associated fossils. 



Mr. Day then exhibited, in the form of a generalized section, the 

 different Ammonite-zones into which the Middle and Upper Lias of the 

 Dorsetshire coast could be divided, and gave lists of the fossils peculiar to 

 each. 



Geological Society. — March 4. — " On the Permian Rocks of ZSTorth- 

 Eastern Bohemia." Bv Sir Roderick I. Murchison, E.C.B., E.R.S. 



The author, accompanied by Dr. Anton Fritsch, of Prague, made a 

 transverse section of the rocks exposed by railroad-cuttings between Josef- 

 stadt on the S.S.E. and Semil on the N.X.TV. These rocks, simply termed 

 Roth-todt-liegende by the Austrian and Saxon geologists, are however of 

 very varied mineral characters and of very considerable dimensions. They 

 consist, in ascending order, of, 1st, coarse conglomerate and sandstone, 

 followed by thin courses of schist, with fishes (Palseonisci, etc.), and inter- 

 stratified igneous rocks (basaltic clinkstone, porphyry, etc.) ; 2nd, alterna- 

 tions of coarse grits and sandstone, with large Araucarites and other plants ; 

 and 3rd, of bituminous schists, in parts containing coal, with some layers 

 of limestone, copper-slate, etc., and many fossil fishes in bituminous flag- 

 stone passing up into red-and-green-spotted sandstones and marls. 



This series of rocks, though subject to local undulations, assumes at 

 Liebstadtl a steady dip to the S.E., or away from the Riesengebirge : this 

 is well seen on the railway between Liebstadtl on the S.E. and Semil on 

 the N.W., which section was described by the author in detail. The 

 igneous rocks, chiefly amygdaloids and porphyries (Melaphyr), occur at 

 various horizons in the series, and are supposed to have been, for the most 

 part, of contemporaneous formation with the regular aqueous sediments. 



Alluding to the animal remains, as enumerated by Geinitz, the author 

 stated that he was disposed to view the group as having chiefly an estuarine 

 character, the various sauroid fishes and the coarse conglomerates leading 

 to that inference ; at the same time he admits that portions of it were pro- 

 bably freshwater and terrestrial accumulations. After pointing out the 

 chief localities of the large fossil stems of the Araucarites and other plants, 

 allusion was made to the opinion of Goppert and Geinitz, that the fauna of 

 this group is. as a whole, distinct from thai of the carboniferous age. He 

 shows that the thickness of the whole of these rocks in Northern Bohemia 

 is very considerable. At Erlbach, in the adjacent country of Saxony, 

 the inferior half only of these deposits, or the lower Rothliegende, has 

 actually been sunk through by a shaft, in search of coal, to the depth of 

 2300 feet, as brought to his notice by Professor Keilhau. 



in referring to the general relations of these rocks, he suggests that, is 



VOL. VI. T 



