42 



we find only what belongs unquestionably to 

 volcanoes, feldspar-lavas, dolerites, basaltes, ag- 

 glomerated scoriae, tufas, and pumice stones. 

 Among the limestone formations we must 

 distinguish those, which are essentially subor- 

 dinate to volcanic tufas # , from those which ap- 

 pear to be the work of madrepores and other 

 zoophytes. The latter, according to Mr. Moreau 

 de Jonnes, seem to lie on shoals of a volcanic 

 nature. Those mountains, which present traces 

 of the action, of fire more or less recent, and 

 some of which reach nearly nine hundred toises 

 of elevation, are all situate on the western skirt 

 of the Smaller West India islands*}-. Each island 



* We have noticed some of these above (vol. iii, p. 575), 

 after Mr. von Buch, at Lancerota, and at Fortaventura, in 

 the System of the Canary Islands. Among the smaller islands 

 of the West Indies, the following islets are entirely calcareous, 

 according to Mr. Cortes : Marigalante, la Desirad, the 

 Grand Terre of Guadaloupe, and the Grenadillas. According 

 to the observations of this naturalist, Curasoa and Bonaire 

 (Buen Ay re) present only calcareous formations. Mr. 

 Cortes divides the West India islands into, 1st, those con- 

 taining at once primitive, secondary, and volcanic formations, 

 like the greater islands ; 2nd, those entirely calcareous, (or 

 at least so considered) as Marigalante and Curasoa; 3rd, 

 those at once volcanic and calcareous, as Antigua, St. Bar- 

 tholomew, St. Martin, and St. Thomas ; 4th, those which 

 display volcanic rocks only, as St. Vincent, St. Lucia, and 

 St. Eustatia. 



f See the observations of Mr. Amie, in his Rapport sur 

 VEtat duFolcan de la Guadeloupe en 179?, V- W* 



