1-24: On the Flora (Did Fauna of Santa Cruz. 



The discovery of a submarine ridge, connecting Santa Cruz 

 with Saba is interesting ; but its geological age is as uncertain 

 as is that of the deep chasm now separating Santa Cruzfrom 

 St. Thomas. 



I have shown, conclusively, I think, that the land-shells sup- 

 ply abundant evidence of the former connection of Santa Cruz 

 with St. Thomas, and the other islands of the Virgin group, but 

 none of its connection with Saba. 



A variety of B. frater cuius occurs in Saba, and a Succinea, 

 which I believe to be Riisei, with several of the widely distributed 

 StenogyrcB, and Helicina pida, Fer., belonging to the Carib- 

 bean fauna, is also found there. Very recently I have received 

 from thence, through tlie kindness of my friend, Mr. F. A. 

 Ober, many specimens of Ampliibulima patula, Brug. , hitherto 

 known only from St. Christopher, Dominica and Marie-Galante. 



The five-hundred-fathom line mentioned, embraces Anguilla, 

 St. Martin, and St. Bartholomew, but their land-shells are far 

 more allied to those of Porto Kico and the Virgin Islands than 

 to Caribbean species. Macroceramus signatus, Guild., occurs 

 in Anguilla and St. Bartholomew, in several of the Virgin Islands, 

 and in liayti, — the genus is not represented in the Caribbees. 



Pineria Schrammi, Fisch., of Guadeloupe, which I believe to 

 be identical with P. Viequensis, Pfr., of Vieque and Barbados, 

 inhabits each of the three islands on the Anguilla bank. 



With regard to changes of the flora and fauna of Santa Cruz, 

 two causes have been suggested, but entirely under misappre- 

 hension, and I deem it desirable to place the facts on record. 



The Eev. John P. Knox, in his " Historical Account of St. 

 Thomas, W. I." (New York, 1852), relates circumstances con- 

 nected Avith the establishment of a French colony in Santa Cruz, 

 in 1650. The settlement, he says, proved at once very un- 

 healthy. He adds: — "In order to arrest the mortality which 

 was so rapidly thinning their numbers, — a mortality which arose 

 from the dense and aged forests that covered the island, scarcely 

 affording an opportunity for the winds to carry off the poison- 

 ous vajDors with which its morasses clogged the atmosphere, — 



