COLUMBIAN REGION. 111 
part, and Cistula, part.)* The solitary Clausilia is found in Porto 
Rico, the Balea in Haiti, and the Tornatellina in Cuba; Stenopus 
is peculiar to St. Vincent’s. Bermuda has 4 Helices, of which one 
is common to Texas and one to Cuba. The Chondropomas are 
found in Cuba and Haiti. 
The West Indian Achatine belong to the sub-genera Glandina, 
Liguus and Spiraxis ; the Bulimi are sharp-lipped and mostly 
small and slender (Subulina, Orthalicus). Helix (Sagda) epis- 
tylium, H. Carocolla, and Succinea (Amphibulima) patula are 
characteristic forms. 
Although connected with Florida by the chain of the Bahamas, 
and with Trinidad by the lesser Antilles, very few species are 
common to the mainland of either North or South America; 
the relation is generic chiefly. 
The Limacide are represented by Vaginulus (Sloanei) ; and in 
the fresh waters there are species of Physa (3), Planorbis (8), 
Ancylus, and the peculiar Gundlachia, Valvata pygmeea, Am- 
pullaria (fasciata), Paludestrina (minute species), Hemisinus, and 
2 species of Pisidiwm. 
In the brackish waters are Cerithidium, Neritina (e.g. melea- 
gris, pupa, virginea, viridis), Melampus (coniformis), and Pedipes 
quadridens. 
22. COLUMBIAN REGION.+ 
The tract shaded in the map comprehends several minor 
regions; 1, the rainy and wooded states of New Granada and 
Ecuador; 2, the elevated and nearly rainless province of Vene- 
zuela, with a flora like that of the higher regions of the Andes; 
3, the Guianas, including the Valley of the Amazon, where the 
forests are most luxuriant, and rain falls almost daily (amount- 
ing to 100 or eyen 200 inches in the year). Most of the low 
lands, like those of the Mexican Province, belong to the ‘‘ Cactus 
Region”’ of botanists, and havea mean temperature of 68°—84°. 
Land shells are abundant in the forests and underwood of the 
lower zone of the mountains, where the temperature is 10° 
less and the rains more copious. Bulimi are the predominant 
forms, especially the succinea-shaped species, (e.g. B. succinoides). 
* A maenificent collection of Jamaica land shells has been presented to the British 
Museum by the Hon. E. Chittty, whose researches were conducted with the late 
Professor C. B. Adams. 
7 In 1821 the States of New Granada, Venezuela, and Ecuador united to form the 
* Columbian Republic,” but dissolved again in 1881. 
