ANNIVEKSAET ADDEESS OP THE PEESIDEKX. Ixi 



cannot be strictly carried out, in consequence of so many of these 

 fossil remains, which extend no higher up than the Silurian series, 

 being in such a fragmentary state that it is impossible to decide 

 upon their complete characters. Professor Hall then shows that, 

 although found in other countries and other Silurian beds, the 

 Quebec beds mark the period of the greatest prevalence of the 

 G-raptolitidse, and that the subsequent conditions of these Quebec 

 beds in Canada have been so favourable to their preservation, 

 that they have been there found in a more perfect condition than 

 in any other formation. 



M. Barrande has published, in the ' Bulletin de la Societe Greolo- 

 giqu.e de France,' an account of the occurrence of the Bohemian 

 colonies in the Silurian basin of the north-west of France and in 

 Spain. He says that the Primordial fauna, which appears to be 

 wanting in Prance, is spread over a large extent of ground in 

 Spain as in Bohemia. To it belong the limestones with J?ara- 

 doxides in the Cantabrian chain of mountains, and the slates with 

 Farachxides near Murero, north of Daruea in Aragou. On the 

 other hand, the Second Silurian fauna is considerably developed 

 in Prance as well as in Bohemia and Spain. This is followed in 

 all these countries by the Third fauna, characterized alike by the 

 presence of Gardita interrii-pta, Ortlwceratites, and several Grap- 

 tolites, traces of which are found in the Second fauna, both in 

 several Departments of Prance and in Spain. 



Permian. — "We are indebted to Sir P.. Murchison and Professor 

 Plarkness for an important communication respecting the true 

 limits of the Permian rocks in the north-west of England. The 

 principal feature in this new arrangement is the absolute con- 

 nexion with the Zeehstein (Magnesian Limestone) or its equiva- 

 lents, of great masses of superposed red sandstone, which, in the 

 north-west of England, they propose to remove from the New Eed 

 Sandstone or Trias, to which they have hitherto been assigned, 

 and to consider them as the natural upper limit of the Permian 

 and Palaeozoic deposits. 



Professor Sedgwick had long ago pointed out, in the Western 

 region at St. Bees Head and in Purness, the existence of the 

 equivalents of the Magnesian Limestone, but without referring 

 the beds to the Permian formation, to which the Magnesian Lime- 

 stone belongs. Li the introduction to this paper. Sir P. Mur- 

 chison obseiwes that this transference of the sandstones of St. 

 Bees and Corby to the Permian group does not depend on fossil 

 evidence, but on clear and unmistakeable sections, which show 

 that these upper sandstones are connected with the lower sand- 

 stone or Pothliegende through the intervention of the Magnesian 

 Limestone or its equivalents ; and that thus united, all these 

 strata, from the base to the summit, form one continuous series. 

 And he adds, that a careful examination of the various localities, 

 both in England and in Scotland, has satisfied him tbat, notwith- 

 standing their very striking lithological dissimilarit}^, the Magne- 

 sian strata to the east of the Pennine chain and the Eed Sand- 



