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PROCEEDINGS OF THE AMERICAN ACADEMY. 



Many other cases of single tombolos occur in Boston harbor (C. S., 337 ; G. S., 

 Boston Bay, Mass.). Among these may be mentioned Winthrop head, point Siiir- 

 ley, Peddocks island, Hull, and the islands tied by Nantasket beach. 



Little Koniushi island, Alaska (C. !S., 



I)- 



Biorka island, Alaska, is made up of 

 two islets tied together by a bar (C. S. 

 724). 



George island, Alaska, sliows com- 

 posite building (C'. S., 741). 



Aniaknak island, Alaska, has three 

 component parts (C. S., 8901). 



Morro Ingles island, Paz point, and 

 San Vicente island, Mexico (II. 0.> 

 640). 



Mare island (C. S., 5524, old number 

 C25) is a case in San Pablo bay where 

 an island has been tied by a tombolo to 

 the mainland. 



Spider island, Alert harbor, Chile 

 (II. O., 92G). 



Mt. Division, 1880 feet high, is con- 

 nected with the mainland of Peru by 

 a low sandy isthmus (II. O., 1178, 1185, 

 11G2), which is probably a tombolo. 



Morro of Barcelona, Venezuela (H. 

 O., 374). 



An island off the Bonneville shoreline 

 near George's ranch was tied by a tom- 

 bolo, in which three attempts at tying 

 are figured by Mr. Gilbert.* 



Gilsay island in the sound of Harris 

 (Scot., 80). 



Taransoy is apparently built up of 

 three islands tied together (Scot., 98). 



Ilowth peninsula has the form of an 

 island tied to the mainland northeast 

 of Dublin (Ireland, 112). Transporta- 

 tion is indicated both from the cliffs of 

 the mainland toward the island and from the island along the tombolo. Broad 

 tidal flats, cut with runways, occur on the right and left of the tombolo. 



Mweenish island is made up of three drumlin-shaped portions connected by 

 narrow necks, presumably tombolos (Ireland, 115). 



Illaunatee or Straw island, one of the Aron islands (Ireland, 113). 

 The Chesil bank t connects the isle of Portland with the mainland of Dor- 

 setshire (Eng., 17). 



* Mon. I., U. S. G. S., 113, Fig. 23. 



t For the literature on this tombolo consult De la Beche, Geol. Notes^ 1830, IL 

 p. ix ; Geikie, Textbook, 3d ed., 1893, 451. 



Kiloineteri 







I 



Figure 14. 



Single Tombolo : Nahant, 

 Massachusetts. 



