Vegetation of Northern Cape Breton. 



325 



and there are similar spits at the mouth of the Barrasois River 

 and Indian Brook. Near the Barrasois and at South Bay, 

 Ingonish (Fig. 42), lakes of considerable size have been cut off 

 from the sea by barriers, the one at the latter place being fresh 

 and several feet higher than high tide level. Small ponds and 

 lagoons, cut off by barriers, are of frequent occurrence (Fig. 26). 

 In a general way, a shingle beach, like a sandy beach, is sub- 

 divided into three more or less distinct zones which, following the 

 classification of Cowles ('01, p. 170), may be termed respectively 

 the lower, middle, and upper beaches (Fig. 2"/). The lower 



Figure 26.— Shingle beach enclosing small fresh pond ; scrubby spruces, 

 etc. in foreground, habit largely the result of grazing; in background, 

 second growth spruce, etc. ; Wreck Cove. Photograph by Dr. L. H. 

 Harvey. 



beach is the part submerged by ordinary high tides. It ranges in 

 width from a few yards to more than a hundred feet. The 

 deposit here (at least in summer) is usually gravelly or sandy 

 toward its lower limit, becoming pebbly above and gradually 

 merging with the shingle; Except for the occasional presence 

 near low tide level of Zostera marina and brown algae such as 

 Fucus, vegetation is absent. The middle beach comprises that 

 part of the beach immediately above the lower beach which is 

 swept by the waves of winter storms or is covered over by ice 

 in winter. Like the lower beach, it varies greatly in width. The 

 deposit here consists almost wholly of water-rounded cobbles 



