192 



PROCEEDINGS OP THE AMERICAN ACADEMY. 



Many islands along the east coast of Sweden (Swe., U, 17, 22, 29, 37, 46, 67, 68, 

 76, 85, 86, etc.) ; also on the west coast (Swe., 18, 24, 25, 32, etc.). 



Maine (C. S., 101, 102, 103, 104, 105, 106). 



Numerous exiimples on the coast of Norway (Nor., 5, B ; 48, B ; 49, C ; etc.). 



Many islands among the Orkney, Shetland, and Hebrides on the north and west 

 of Scotland (Scot., 58, 59, 101, 104, etc.). 



Off Marseilles (Fr., 247) there are several very young islands. 



Lipari islands, Tyrrhene sea (Ital., 244). 



Capo Passero island, Sicily (Ital., 277). 



Gemini and Corbella, south of Elba (Elba). 



Islands west of Fosana, Austria (Austr., 26, IX). 



Numerous islands in the Adriatic where ideal possibilities for future tying exist 

 (Austr., 31, XIII, XIV ; 34, XVII ; etc.). 



III. Uncompleted Tomholo (Youth). — AVheii more waste is supplied 

 than the sea can deposit offshore, transportation alongshore begins, and 

 there is a tendency to aggrade the surplus load of detritus. Such build- 

 ing- would naturally be expected to occur in the comparatively quiet 

 water between the island and the mainland. This is found to have taken 

 place in many localities. According to the several conditions of the 

 variable factors in the problem, the tombolo may begin to grow from the 

 mainland, the island, or from both. 



a. Attached to Mainland onli/ : Gigha. — The typical example is seen on the west 

 ;;oa.st of Scotland, where Rhunahaorine point projects as a cuspate foreland from 

 the mainland toward the island of Gigha (Scot., 20). This foreland is of the nature 



of the tidal forelands described on 

 page 214, and a tombolo may never 

 be completed across the deep chan- 

 nel. 



A shoal extends from the large 

 island, Berneray, toward the rocky 

 stacks, Sgeir a' Ciiail (Scot., 89). 

 This islet is fast being consumed by 

 the sea, and probably never will be 

 tied. 



Lingay strand extends below high 

 tide level toward Lingay island 

 (Scot., 89). 



Callao, the seaport of Lima, Peru, 

 is built on the tombolo growing toward San Lorenzo island (Stieler, 94; Midden- 

 dorf. Das Kiistenland von Peru, 1894,36). 



Angel island in San Francisco bay, California (C. S., 5581). 



b. Attached to Island only : Tuno. — From Tunc") island (Denm., SamsJ)) there pro- 

 jects toward Sams(3 island a lanceolate cusp, showing the attempt to tie the smaller 

 to the larger island. 



Figure 13. Diagram of Uncompleted 

 Tombolo. 



