]89(. PROCEEDINGS OF THE NATIONAL MUSEUM. 429 



(2) Jamaica; (3) Haiti; (4) Puerto Rico, with Vieque, the Virgin Islands, 

 Sombrero, Auguilla, St. Martin, St. Bartholomew, and St. Croix. The 

 islands south of the latter, to and including- Trinidad, he places in a 

 fifth province. Fischer follows essentially this arrangement,* except 

 that he places the Bahamas in a separate division and adds Bermuda to 

 that of North America, though he thinks the latter group of islands 

 shows about equal malacological affinities with Florida and the Antilles. 



While the molluscan faunas of each of the four large islands of the 

 Greater Antilles contain much that is peculiar, yet I believe that the 

 relationship of the genera and species is much closer than has generally 

 been supposed. Among genera that are restricted to this archipelago 

 only five are confined to Cuba — Glandineila, Diplopoma., Bkcsospira, 

 and Xenopoma^ each having but a single species, and Polymita, with 

 four species; one is restricted to Haiti — Rolleia, with one species — and 

 two to Jamaica — Zaphysema, with six species, and Jamaicia, with two. 

 Of genera of wide distribution that are found only on a single island 

 there are three in Cuba — Cionella, GuKdlachia, and Viviparu, each with a 

 single species — and four in Jamaica — Carychium, Strobilops, Hemi.sinus, 

 and Valvata, each with one representative — while Puerto Rico has a 

 single Clausilia, and three Peltellas. 



Nearly all the peculiar genera, and those of wide distribution that are 

 at all numerously represented, are found in three, if not all four, oi the 

 larger islands. The following table exhibits the distribution of all the 

 terrestrial and tluviatile genera. The marine Xeritinas, the semi aquatic 

 Auriculidae, and the Truucatellas, which are distributed in the same 

 way as the ordinary salt-water Gastropods, are not included. There 

 are no peculiar fresh-water molluscan genera in the West Indies. 

 The lists of this paper are as accurate as I can make them. The fact 

 that so many changes have recently been made in the literature and 

 classification, and that no two authors agree as to specific and generic 

 values, make it well nigh impossible to give lists that are correct. 



* Manuel ile Coucholiologie, p. 269. 



