232 MR. JUKES-BROWNE AND PROF. HARRISON 



that these fossils " appear to be in no wise different from the shells 

 inhabiting the surrounding waters," but that the limestone is not; 

 exactly like any of that in Antigua. 



As he describes the limestone as white and compact, it has prob - 

 ably been altered and indurated by the percolation of water, like so 

 much of that in Barbados. The Bulla is doubtless Bulla striata, so 

 common in the lower terraces of Barbados and one of the corals, 

 described by Prof. Duncan by the name of Cyphastrcea costata, has 

 now been identified by Air. J. W. Gregory among the corals we brought 

 from Barbados. 



In a note to his "Geology of Antigua" {op. cit. p. 463) Dr. 

 JS^ugent states that during a visit to Spanish Point, the south-eastern 

 point of Barbuda, he found a yellow marl containing marine shells, 

 Fijrula, Trochus, Ci/pnea, and Buccinum, together with the same 

 Bulimics and Heliv as those which occur in the Marl formation of 

 Antigua and another laud-shell which he had not met with in a 

 living state. 



Mr. II. J. L. Guppy * refers to the island in the following terms : — 

 "■ Barbuda contains a formation resembling the coral-limestone 

 of Barbados. It consists of a white calcareous deposit full of 

 shells, all of which are, as far as I have examined, of existing 

 species." He adds, " the existence of a Miocene formation in that 

 island seems nevertheless to be indicated by the corals described 

 by Dr. Duncan ; " but we have already discussed this ease 

 (p. 229). 



(d) Anegada, the northernmost island of the Virgin group, is 

 interesting chiefly because it is an example of the appearance pre- 

 sented by a coral island which has just been raised a little above 

 the level of the sea. It was carefully surveyed by Sir R. Schom- 

 burgk in 1831 1, who des3ribcs it as a long low island, no part of 

 which is more than 60 feet above the sea. It consists entirely of 

 coral-rock and coral-sand, the surface rising in some places into 

 mounds and in others dipping below sea-level into ii-regolar depres- 

 sions, which are filled with salt water and form large ponds or 

 lagoons. "The bottoms of all these ponds are shelfy and uneven, 

 with heads of coral-rocks often rising in them above the surface of 

 the water. . . . The southern side of the island is a continued 

 mass of shelves loosely covered with vegetable earth more or less 

 mixed with sand .... and the shelves are intersected with 

 openings, sometimes narrow, sometimes of considerable width and 

 depth. . . . Eresh water is found in great abundance on almost 

 ever}' part of the island, frequentlj' even in the immediate vicinity of 

 the sea and surrounded by salt ponds. On the north side, near 

 Loblolly Bay, are a range of shelf-holes, called the Wells, which 

 are filled with fresh water." He found the depth of these holes was 

 from 12 to as much as 36 feet : their width at the surface being from 

 10 to 25 feet, and the hole narrowing downwards in the form of a 

 funnel. 



* Quart. Joiirn. Geol. Soc. vol. xxii. (1866) p. 578. 

 t See Journ. Roy. Geogr. Soc. vol. ii. (1832) p. 152. 



