io8 



Perce Rock limestone which conforms faunally with the 

 Grande Greve beds. The absence at Perce of the major 

 part of the Devonian limestone series serves to indicate 

 how extensively the formation has been lost by faulting 

 out rather than by lack of continuity. 



Unconformity between the Devonian limestones and the 

 Cape - des - Rosiers slates. — Similarly the entire represen- 

 tation of the Silurian and Ordovician, as indicated 

 in the Perce section (a minimum of 1,000 feet 

 and probably much more), has been lost in the Forillon 

 section, by the overthrust which has carried these De- 

 vonian limestones over the erect and distorted Rosiers 

 slates of Cambrian (Cambro-Ordovician?) age. So far as 

 we have any evidence, the vast overthrust of this Forillon 

 fold is due to the resistance imposed by the crystalline 

 horst lying at the north of the St. Lawrence river (Canadian 

 shield) and the degree of the reaction is expressed both in 

 the fold itself and in the great fault ('Logan's fault') 

 which outlines the course of the river. 



Relation af the limestones to Gaspe sandstone. — 

 As observed, an actual unconformable contact of the 

 limestones with the overlying sandstones is seen at Little 

 Gaspe i \ miles (2-4 km.) west of Grande Greve where the 

 first ridge of sandstone mountains comes to the coast. 

 Infaulted masses of these red sandstones in the limestones 

 are also to be seen eastward of Grande Greve indicating 

 the removal of an entire mantle of the Gaspe sandstone 

 from above the limestones. 



The Flora of the Gaspe Sandstone, by David White. — 

 Gaspe is the most interesting locality for Devonian 

 plants yet known in Canada. The Gaspe sandstones are 

 remarkable for the abundant plant fragments, mainly 

 representative of Psilophyton which occur in great num- 

 bers at some horizons, and which interestingly enough 

 appear, at several levels, to be rooted in old soils. Frag- 

 ments, frequently but slightly compressed, from this district 

 are present in many of the museums of Europe, as well as 

 in most of those in America. Gaspe was twice visited by 

 Sir William Dawson, who described all the species reported 

 from this region. The Psilophyton-bearing beds occur 

 at many horizons in the section, one of the most interesting 

 being near Watering brook on the north side of the bay. 

 Several plant-bearing layers were described by Dawson 

 as old soils. Associated with other plant remains are 



