FLORA OF ST. CROIX AND THE VIRGIN ISLANDS, 



WEST INDIES. 



By Barox H. F. a. Eggers. 



To the east of the island of Porto Eico, between 18° 5' and 18° 45' 55^. 

 lat. and Gi° 5' and 05° 35' W. long., stretches a dense cluster of some 

 larger and numerous smaller islands for a distance of about 85 miles, 

 which are known by the name of the Virgin Islands. The principal 

 islands are Vieques and Culebra, belonging to Spain, St. Thomas and St. 

 Jan, belonging to Denmark, and Tortola, Virgin Gorda, and Anegada, 

 belonging to England. The superficial area of the larger islands is only 

 from 10 to 40 square miles, whilst the smaller ones are mostly uninhabited 

 islets, or even rocks, some of which are nearly devoid of vegetation, the 

 coast-line of them all being sinuous, and forming numerous, small bays 

 and creeks. The Avhole group is evidently a submarine prolongation of 

 the moimtains of Porto Eico, showing its tops and higher ridges above 

 the h^A'el of the sea, the depth of which between the various islands and 

 Porto Eico is only from 6 to 20 fathoms. The decli\'ities to the north 

 and the south of the ridge on the reverse are very steep, no bottom hav- 

 ing been found 25 miles to the south in 2000 fathoms, and 80 miles to the 

 north the Challenger Expedition found a depth of about 3850 fathoms, 

 the greatest ever measured in the northern Atlantic Ocean. 



The greatest height in the Archipelago is attained in its central part, 

 St. Thomas reaching up to 1550', Tortola even to 1780', St. Jan and 

 Virgin Gorda being a little lower, whilst the hills in Vieques and Cule- 

 bra, to the west, are only 500'-(>00' high, and Anegada, the northeastern- 

 most, is, as its Spanish name, the inundated, implies, merely alow or half- 

 submerged island, elevated but a few feet over the level of the sea. The 

 central islands, therefore, present the appearance of a steep ridge, pre- 

 cipitously sloping to the north and the south, and cut up by numerous 

 ravines, which during heavy rains are the beds of small torrents, but 

 which generally are without running water, and which at their lower end 

 widen into small level tracts on the sea-coast, often forming a lagoon on 

 the sandy shore. Between these level tracts the coast is usually very 

 Bull. Nat. Mus. No. 13 1 1 



