442 THE CANADIAN NATURALIST. fVol. vii. 



General set of Polar current over New Brunswick and Maine. 



In the region to which this table relates there are three tracts 

 each characterized by certain peculiarites in the gravel ridges. 

 In the middle tract — which includes the Oromocto Valley and 

 N<repi> Valley — the ridges are short and irregular, owing to the 

 course of the current which here ran obliquely to the direction 

 of the hill ranges ; and no ridges are recorded in the table, because 

 they have not so evident a bearing on the general course of the 

 current as the ridges in the other two districts have. In the 

 latter the gravel ridges are much longer and more conspicuous, 

 and approximate in direction to the course of the rocky ridges: 

 but while in the western tract they are directed to the S. E., in 

 the eastern they point to the S. W. They differ also in the 

 kind of ridge which prevails ; for while horsebacks are numerous 

 in the western district, broader and rounder ridges, whalebacks, 

 etc.. are common in the eastern, and in the middle tract the 

 gravel banks consist almost exclusively of lee and weather shoals. 



It will be seen that the western area corresponds quite nearly 

 to the ''first tract " of glacial striae (see page 11 of my former 

 article) and in it the striae agree in direction with the Syrten- 

 sian ridges ; but in the eastern district near the coast there is a 

 striking difference between the course of the striae and the gravel 

 ridges, the two running nearly at right angles to each other. 

 From this it may be inferred that the hills of Southern New 

 Brunswick which during a preceding period formed no serious 

 obstacle to the onward progress of the Glacial ice, had risen 

 sufficiently during the Syrtensian epoch to act as a barrier which 

 turned aside to the right and left the principal volume of the 

 polar current. As a result the minor currents traversing the 

 gaps in these hills in Queen's and King's counties united with 

 the grand current in the Bay of Fundy, and ran along the south- 

 ern side of the granite hills which extend from Bald Mt. on the 

 St. John River to Red Rock Mt. on the Magaguadavic. This 

 would give to the sea of the Syrtensian period a depth along 

 this coast of from TOO to 1000 feet greater than it has at present. 

 While this may have been the depth in southern New Brunswick, 

 when the principal gravel ridges were in process of formation, indi- 

 cations tbat the sea bottom underwent important oscillations else- 

 where are not wanting. At the lower end of Ijake Eutopia, near St. 

 George, in Charlotte county, are N.E. — S.W. gravel ridges extend- 



