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PROCEEDINGS OF THE AMERICAN ACADEMY. 



woru from the island, and then in youth this waste tails oif on right and 

 left toward the mainland or in the direction of the quietest water. K 

 the island is so far from the mainland that these spits cannot reach land, 

 they are most likely, in swinging back and forth with varying currents, 

 to join each other and thus form a loop-bar. 



Sliapka I. 



700 Ft. 



Nautical MUe 



Figure 12. Loop-bar : Sliapka Island, Alaska. 



The form of Sliapka island^^laska (Figure 12), indicates that it had two spits 

 formed on its lee side from the waste of the eastern cliff face, and tliat these two 

 have now joined, forming a looped bar enclosing a lagoon (C. S., 8881). 



Cup butte, Utah, is an example in the fossil condition.* 



San Juan Nepomezino island, Lower California, has a salt lagoon at its southern 

 end evidently similarly inclosed (H. O., 42). 



Cockenoes island has two long stringing bars pointing toward the coast at Nor- 

 walk, Conn., but the bars have not as yet joined (C. S., 116, 3039). 



Endelave island (Denm., Bogense) is being consumed on the east and south sides 

 and the material is transported around the north and west ends. This is shown by 

 the hooked spit on the west end and by the five lines of slaslies, or narrow lagoons, 

 inclosed by successive outgrowing beaches. If this process is continued a little 

 farther we shall here see another Shapka island with enclosed lagoon. 



Flying-bar : Sable Island. — When an island is completely reduced to 

 a submarine condition, the bar formed from its waste may still remain. 

 A case like Shapka, when the former island was completely consumed, 

 would give a flying-bar. 



* Gilbert, Lake Bonneville, p. 55, PI. VL 



