AGASSIZ: BERMUDAS. 247 



Island Flat shows them to be similar to those of corresponding position 

 which we examined oft' the north and south shores of the main island, 

 and there is nothing to show that thej, any more than the ledges just 

 mentioned, owe any considerable part of their increase to coral growth. 

 We found here many patches of limited extent, with nearly vertical or 

 steep faces, greatly honeycombed, and worn and covered with Algte, 

 Corallines, and coral growth, some of them rising from seven fathoms up 

 to near low-water mark. 



The corals on tlie ledges of Brackish Pond Flats increase in profusion 

 on the patches as they increase in distance from the main channel. But 

 the appearance of the animal and vegetable growth on the ledge is prac- 

 tically the same on all the ledges of the Bermudas ; it is a question qf 

 quantity mainly. The greatest profusion of corals and Gorgonians, as 

 far as I have observed them, has been found on the ledges of the flats 

 of the northern, northwestern, and northeastern parts of the banks. 

 The ledges and patches to the west of Iceland and Somerset Islands are 

 connected with the patches to the westward, and form a continuous line 

 of flats as far as the Western Reef Flats. They constitute a series of 

 proto-Bermudian clifl" ledges which have been worn away from the shore 

 cliffs, or from the edges of former lagoons and sounds, and have been 

 overgrown by a tliin veneer of corals, Millepores, and Gorgonians. 



The west shore of Somerset has been greatly encroached upon by the 

 sea ; its northern extremity has been divided into a number of islands 

 terminating with Ireland Island and the islets flanking it. One of 

 its extensions forms the western line of rocks and islets of Mangrove 

 Bay. It was formerly connected with the spit running from High Point 

 to Wreck Hill, but the sea has eaten its way through, and the islets run- 

 ning north from Wreck Hill are the western barrier of Wreck Bay. All 

 along the shores numerous mushroom-shaped rocks are seen, either iso- 

 lated or still connected by a basal ledge, especially in the ledge running 

 south of Daniel Island. From Wreck Hill Bay to Ireland Island innu- 

 merable ledge patches are found, with from two to six fathoms between 

 them. These patches extend in a wide flat to the westward, forming 

 what is known as Elies Flat until they join the western ledge flats to 

 the eastward of Chub Cut, where there is a narrow and somewhat intri- 

 cate channel with four to five fathoms of water leading from the inner 

 waters to the outer bank. This channel separates the Western Ledge 

 Flats and the flats to the eastward of the Blue Cuts. The bottom of the 

 channel is covered with massive corals, Gorgonians, and Algae. An 

 examination of patches which reach out from the shore, and have been 



