LAND REGIONS. -JOo 



which have a somewhat extensive distribution. Gaudeloupe has 

 68 species, Dominica 20, St. Kitts 6, Martinique 50, etc. Amphibu- 

 lina patida appears to have become extinct a few years since 

 in Guadeloupe, but still lives in Dominica and St. Kitts. 



Y. St. Lucia ^ St. Vincent, Barbados, Grenada, Tobago, Trinidad. 

 These islands differ radically from those which precede them by 

 the introduction of South American Bulimi. This continental 

 character is more pronounced in the islands nearest the Vene- 

 zuelan coast. (The characteristic Bulimi of the other islands are 

 of very few species, but two or three of them have a much more 

 extensive distribution than the other land shells.) There are 

 at St. Lucia, 3 species, at St. Vincent 15, at Barbados 30, at 

 Grenada 14, at Tobago 1, at Trinidad 52. In the latter island, 

 nearl}^ half of the species are of continental, principally Vene- 

 zuelan origin, including the large Bulimus (Borus) oblongus, 

 Geratodes {Ampullaria) corna-arietia, Streptaxis deformis, etc. 

 Here is found the only West Indian species of Anodonta. 



8. Windward Islands. Very few species are known : the 

 curious genns Ravenia is special to the islet Los Roques. 



The distribution of the West Indian shells presents some 

 interesting peculiarities. Thus the group Strophia lives only in 

 the Bahamas, Cuba, Haiti, Porto Rico, St. Croix and Cura^oa, 

 not in the intermediate islands ; Simpulopsis has been found at 

 Haiti, Porto Rico and Trinidad ; Amphibulina occurs only in 

 the Lesser Antilles ; Stoastoma, Trochatella, Lncidella, Proser- 

 pina, Ctenopoma, on the contrary, are restricted to the Greater 

 Antilles ; Gundlachia has only been found in Cuba and Trinidad ; 

 Cylindrella, Bulimulus, Glandina, Macroceramus, Helicina, Cis- 

 tula, Chondropoma, Choanopoma and Tudora are found in 

 nearly all the islands ; there are only 3 Unionidse, 2 of them 

 restricted to Cuba, the other to Trinidad. 



28. American Region. • 



The eastern and central portions of the United States consti- 

 tute a vast and thickly populated moUuscan region : Florida, 

 Louisiana and Texas are included in it, although a few of the 

 species are derived from the neighboring Mexican and Carib- 

 bgean faunas. 



Woodward and Binney have divided this region into provinces 

 which, I perfectl}^ agree with Dr. Fischer, have very slight claims 

 to recognition from any peculiarities of their several faunas ; 

 whilst the region as a whole certainly presents a large assemblage 

 of forms originating within, and in many cases confined to its 

 boundaries. The Helices are not very numerous, and, in contradis- 

 tinction to those of Europe and of California are mainly unicolored 

 shells. A large proportion of them are with toothed aperture. 

 The following are peculiarly American groups ; Mesomphix, 



