166 ANNUAL HECORD OF SCIENCE AND INDUSTRY. 



roofing-slates, passing upwards, without any visible break, into 

 the so-called Lower Potsdam beds. These are fossiliferous 

 slates and conglomerates, to which a thickness of 5400 feet 

 is ascribed. Above them are other fossiliferous strata, as- 

 signed to the Calciferous sand-rock, to which succeeds a great 

 mass of graptolitic slates referred to the Levis division of the 

 so-called Quebec group, and containing the forms of the Arenig 

 or Skiddaw of Great Britain. The fossiliferous strata of the 

 Quebec group in Newfoundland are arranged in sharp folds 

 running in a northeast direction, and are affected bv great 

 dislocations having a similar course. At the summit appears 

 a great mass of what are described as igneous and magnesian 

 rocks, composed of chloritic and hornblendic schists, with 

 serpentines, which, according to Murray, seem " to be lapped 

 over the inferior strata unconformably, and to come in con- 

 tact with different members in different places." This crys- 

 talline series is identical with what had previously been 

 described by the geological survey of Canada, both in the 

 province of Quebec and in Newfoundland, as a part of the 

 Quebec group in an altered state ; the conformable succession 

 being, in ascending order, according to Logan, Levis, Lauzon, 

 and Sillery, so that these crystalline rocks were conceived to 

 be the Lauzon and the Sillery in a metamorphosed condition. 

 With this the observations of Murray are in contradiction. 

 The Sillery which, in accordance with the views of Logan, 

 should overlie conformably the magnesian series, or, rather, 

 form its upper part, is found by Murray to overlie with perfect 

 regularity the fossiliferous strata ; but, in every case where 

 a contact has been seen, the Sillery passes unconformably be- 

 neath the crystalline magnesian rocks. These, then, according 

 to Murray, are not altered strata of the Quebec group, but a 

 newer series resting in discordance upon it, eruptive in their 

 origin, and intermediate in age between the time of the 

 Quebec group and the Loraine shales. In fact, these crystal- 

 line strata arc found unconformably overlaid by fossiliferous 

 strata belonging to the Loraine and Clinton periods. The 

 succeeding Niagara formation is represented at White Bay 

 by 2800 feet of conglomerates and slates with limestones, and 

 the Devonian by about 3700 feet of sandstones and slates 

 with plant-remains. The Carboniferous, which is found in 

 southwestern Newfoundland, lias in one place a thickness of 



