152 bulletin: museum of comparative zoology. 



southern extremity of a bank formed by the 100 fathom line, at the 

 northeastern end of which is placed Barbuda, an island composed of 

 limestone, rising to a height of two hundred feet. The shores of 

 Antigua are deeply indented, especially the northern and eastern faces 

 of the island. It lies upon the middle of the eastern edge of the same 

 bank as Barbuda, the general depth of which is from seven to eleven 

 fathoms, with a coralline and coral sand bottom. It is surrounded by 

 many small islands and islets, and edged on the east, south, and north 

 sides with fringing and barrier reefs, leaving only intricate passages 

 leading into the deep sounds of the island. From the entrance to North 

 Sound the patches of reefs and banks extend in an arc to the westward 

 as far as Diamond Bank, the most westerly of these coral reefs. The 

 Highlands are apparently composed of three terraces, the highest of 

 which is two hundred feet. 



From the southeast end of the eastern shore of Barbuda (Hydro- 

 graphic Chart No. 367, Admiralty Charts Nos. 1997, 2600) a coral 

 ledge skirts the shore at a distance of half a mile ; a reef also extends 

 one and a half miles off the north shore, the depth being thirty fathoms 

 within a mile of it ; and reefs run off the south coast nearly seven miles 

 in a southwest direction. Barbuda is connected with Antigua by a bank 

 with seven to thirty fathoms of water. 



Between Antigua and Guadeloupe an isolated bank rises to a depth of 

 forty-three fathoms, and a similar bank is found to the southeast of the 

 bank limited by the 100 fathom line, of which the principal summits 

 are St. Bartholomew (992 feet), St. Martin (1360 feet), and Anguilla 

 (213 feet). With the exception of Anguilla, they are volcanic sum- 

 mits. They are surrounded by a number of smaller islets of the same 

 structure. 



Sombrero is steep and rises to forty feet from a small bank about four 

 miles long. It is composed of recent limestone (Julien), very much honey- 

 combed, and rises abruptly within the 500 fathom line. In a line between 

 it and Santa Cruz rise two submarine banks, the one with a minimum 

 depth of three hundred and seventy-six fathoms, the other with a depth 

 of three hundred and eighty-three fathoms. 



Anguilla (Admiralty Charts Nos. 130, 2038, Hydrographic Chart No. 

 1002) is not more than two hundred and thirteen feet high. The 

 south shore and the eastern end of the north shore are fringed with 

 coral reefs. An extensive reef runs westward from Scrub Island within 

 the 10 fathom line for over twenty miles, with passages to the west of 

 the Pear Cays and eastward of Dog Island. 



