AGASSIZ: BAHAMAS. 153 



Santa Cruz, the Virgin Islands, and the Greater Antilles.^ 



Santa Cruz is the broad summit of the bank which extends east of the 

 island for a distance of nearly twelve miles, and forms a narrow belt round 

 it. With the exception of a small part of the western end of the north 

 shore and of the western side, Santa Cruz is fringed along its whole 

 coast with corals, forming either fringing or barrier reefs off" the north 

 side, and a broad belt of fringing and barrier reefs skirting the south 

 side, of the island. Round the eastern extremity of the bank to the east 

 of the island an extensive reef (Lang Bank) follows the outline of the 

 100 fathom curve. On this we find six to nine fathoms. It extends on 

 the south face of the bank from the east end to opposite the eastern 

 point of Santa Cruz (Admiralty Charts Nos. 130, 485, and Hydrographic 

 Chart No. 1002). 



The Virgin Island Bank, which includes within the 100 fathom line the 

 Virgin Islands and Porto Rico, is separated from the banks to the south- 

 east of it by a deep canon of over one thousand fathoms, connecting the 

 Atlantic with the Santa Cruz deep of more tlian two thousand fathoms, 

 separating that island from the Virgin Islands. Porto Rico is the east- 

 ernmost of the greater West India Islands, and occupies nearly the whole 

 width of the western end oi the Virgin Island Bank. 



The Virgin Island Bank (Admiralty Charts Nos. 106, a, b, c, 130, and 

 Hydrographic Charts Nos. 1002, 2008) presents very much the same 

 characteristics as the Grenadines Bank. It is the summit of an elongated 

 bank seventy-five miles in length, reaching from Porto Rico to Anegada, 

 and from twenty-three to thirty miles wide. Some of the larger islands 

 which crop out upon the southern edge of the bank, like Crab Island, 

 Tortola, Culebra, St. Thomas, and Virgin Gorda, attain a height of more 

 than fifteen hundred feet, while there are a great number of smaller 

 islands, islets, and rocks barely reaching the surface, all of which are of 

 volcanic origin, Anegada alone being composed of recent reef limestones. 



The sea face of Anegada (Admiralty Chart No. 130, Hydrographic 

 Charts Nos. 1002, 2008) is fringed with a coral reef extending to a 

 depth of about thirteen fothoms. Off the east point the reef spreads out 

 upon a broad bank over three miles in width, which also extends along 

 the western face of the island and is studded with coral heads. A wide 

 ban-d of coral heads extends from East Point, known as the Horseshoe 

 Reef, following in a general way the line of the 100 fathom curve. The 



1 The reefs of Cuba liave already been described in a separate chapter. 



