206 Dr. Daioson — Geology of Prince Edivard's Island. 



Boulder-clay, stratified sand and gravel, and loose travelled boulders. 

 The prevalent Post-pliocene deposit is a Boulder-clay, or in some 

 places boulder-loam, composed of red sand and clay derived from 

 the waste of the red sandstone. This is filled with boulders of red 

 sandstone derived from the harder beds. They are more or less 

 rounded, often glaciated, with striae in the direction of their longer 

 axis, and sometimes polished in a remarkable manner, when the soft- 

 ness and coarse character of the rock are considered. This polishing 

 must have been effected by rubbing with the sand and loam in 

 which they are embedded. These boulders are not usually large, 

 though some were seen as much as five feet in length. The boulders 

 in this deposit are almost universally of the native rock, and must 

 have been produced by the grinding of ice on the outcrops of the 

 harder beds. In the eastern and middle portion of the Island only 

 these native rocks were seen in the clay, with the exception of 

 pebbles of quartzite which may have been derived from the Triassic 

 conglomerates. At Campbellton, in the western part of the Island, 

 I observed a bed of Boulder-clay filled with boulders of metamorphio 

 rocks similar to those of the mainland of New Brunswick. 



Striae were seen only in one place on the North-eastern coast and 

 at another on the South-western. In the former case their direction 

 was nearly S.W. and N.E. In the latter it was S. 70° E. 



No marine remains were observed in the Boulder-clay ; but at 

 Campbellton, above the Boulder-clay already mentioned, there is a 

 limited area occupied with beds of stratified sand and gravel, at an 

 elevation of about fifty feet above the sea, and in one of the beds 

 there are shells of Tellina Grcenlandica. 



On the surface of the country, more especially in the western part 

 of the island, there are numerous travelled boulders, sometimes of 

 considerable size. As these do not appear in situ in the Boulder- 

 clay, they may be supposed to belong to a second or newer boulder- 

 drift similar to that which we shall find to be connected with the 

 Saxicava sand in Canada. These boulders being of rocks foreign to 

 Prince Edward Island, the question of their source becomes an in- 

 teresting one. With reference to this, it may be stated in general 

 terms, that the majority are Granite, Syenite, Diorite, Felsite, 

 Porphyry, Quartzite and coarse slates, all identical in mineral cha- 

 racter with those which occur in the metamorphic districts of Nova 

 Scotia and New Brunswick, at distances of from 50 to 200 miles to 

 the South and South-west; though some of them may have been 

 derived from Cape Breton on the East. It is further to be observed 

 that these boulders are most abundant and the evidences of denuda- 

 tion of the Trias greatest in that part of the Island which is opposite 

 the deep break between the hills of Nova Scotia and New Bruns- 

 wick, occupied by the Bay of Eundy, Chiegnecto Bay and the low 

 country extending thence to Northumberland Strait, an evidence 

 that this boulder-drift was connected with currents of water passing 

 up this depression from the South or South-west. 



Besides these boulders, however, there are others of a difi"erent 

 character ; such as Gneiss, Hornblende schist, Anorthosite and La- 



