: : 
Bland.] 56 [March 3, 
Notes relating to the Physical Geography and Geology of, and the Distribu- 
tion of Terrestrial Mollusca in certain of the West India Islands. 
By Tuomas BLAND. 
(Read before the American Philosophical Society, March 8, 1871.) 
In 1861 I published (Ann. Lye. Nat. Hist., N. Y. VII.) a paper on the 
Geographical distribution of the genera and species of land shells of the 
West India Islands, and in 1866 (American Jour. of Conchology, I.) fur- 
ther papers on the same subject. From a study of such distribution, 
without reference to the Physical Geography or Geology of the Islands, I 
arrived at the conclusion that they may be divided into the five following 
provinces or sections, each having a distinct faunal character, viz. : 
I. Cuba with the Isle of Pines, Bahamas, and Bermudas. 
II. Jamaica. 
III. Haiti. 
IV. Puerto Rico with Vieque, the Virgin Islands, Sombrero, Anguilla, 
St. Martin, St. Bartholomew, and St. Croix. 
VY. The Islands to the south of those last mentioned, to and inclusive 
of Trinidad. 
I remarked that the Islands tothe West of Puerto Rico have the greater 
generic, as well as specific alliance with the North American Continent 
(Mexico and Central America,*of course, included), and those to the 
East and South, with tropical South America. 
Within the last year I have endeavored to learn, if any and what 
evidence may be gathered from the depth of the sea around, and in the 
vicinity of the Islands, of their former greater proximity to each other 
and the adjacent continents, sufficient to account for or throw light on 
the observed facts of land shell distribution. The result is extremely 
interesting, and in the main confirmatory of the views above expressed. 
The British Admiralty Charts have afforded data, chiefly to the 100 
fathom line of soundings only, while recently, through the kindness of Mr. 
Rawson W. Rawson, Governor in Chief of Barbados and the Windward 
Islands, I have obtained particulars of the deep sea soundings, taken in 
the Caribbean sea, especially for Telegraph Cable purposes, by United 
States and British Naval Officers, which supply information of great 
value, as I propose in this paper to show. Iam also indebted for much in- 
formation to ‘‘The West India Pilot,’’ published by the British Admiralty. 
I reserve, for another opportunity, observations on the faunas of the 
first three of the above mentioned sections, now confining myself to the 
fourth and fifth, with incidental reference to that of the second. Since 
the date of my former papers, my knowledge of the species inhabiting the 
Islands embraced in the latter sections has been largely increased, for 
which my acknowledgments are due principally to Mr. Robert Swift, of 
St. Thomas, Dr. Cleve, of the University of Upsala, Governor Rawson, 
and Mr. R. J. Lechmere Guppy, of Trinidad. 
