American Association. 271 



attitude of the strata which surround it. The cvj' stalliue conditiou 

 of the syenite shews that it was slowly cooled under great pressure, 

 and we cannot now say whether it was a deep-seated part of an 

 outburst which reached the surface, as it was then constituted, or 

 whether it was originally overlaid by masses of gneiss and limestone, 

 which have since been worn away. In either case the probability 

 is, that it would give to the strata now surrounding it, an anticlinal 

 form. It seems probable, therefore, that the western dip, belong- 

 ing to the eastern band of limestone, where it approaches the 

 syenite, is a true one, and that the form between the bands is 

 synclinal. This appears to be corroborated by the fact that where 

 transverse valleys occur between them, the wearing down of the 

 intermediate gneiss widens the calcareous bands, particularly the 

 east one, and narrows the interval. 



The calcareous sheet having thus the form of a trough, 

 the western dip of the western out-crop must be an over 

 tu.rn ; and two spurs of the rock which point to one another, 

 the one turning south from the western belt, and the other 

 north from the eastern, must constitute a subordinate anti- 

 clinal. Without reference to minor corrugations, the general 

 form of the area would be that of two troughs joined together, 

 each about a mile aud a half wide, with an overturn dip on the 

 west side, the one trough running north and south, and the other, 

 as far as unconcealed by the superior fossiliferous strata, south- 

 south-west and north-north-east. The opposite sides of this cal- 

 careous trough run into two valleys, which unite at its northern 

 extremity. But though the limestone then crops out, the valley 

 continues northward into Harrington, and after a short interval 

 shows an isolated patch of limestone of about a mile and a half in 

 length, by a mile in breath, possessing, of course, a synclinal form. 

 Beyond this, the valley splits into two, and while one branch runs 

 rather north of N. E,, the other turns W. of E. Eacn of these 

 valleys is paved with limestone, the distribution of which shews a 

 continuation of the synclinal foim, with a bend more to the east- 

 ward than before. 



The calcareous band on the western side has been traced 

 to the north boundary of the township of Harrington, whence 

 it crosses into Montcalm. It there appears to turn to the 

 westward, but it has not yet been farthei;^ accurately examined. 

 The eastern branch has been followed for between six and seven 

 miles into Wentworth, when it appears to turn upon an anticlinal 



