114 REVIEWS 



older eruptive formations. In Guadeloupe the geological records are 

 equally well preserved, on one side, while on the other there are the 

 more recent volcanic cones, which can also be seen in St. Kitts, Statia, 

 Dominica, Martinique, St. Lucia, St. Vincent, etc. 



In St. Martin and Antigua the old volcanic basement forms nioun- 

 tains still uncovered by modern cones, as also in St. Croix. The rocks 

 are essentially an andesite in form of both lavas and tuffs. Their sur- 

 face topography is molded by atmospheric agents into low mountains 

 and valleys. Overlying such a basement in St. Croix and St. Thomas, 

 according to Cleve,'' there is a conglomerate containing pebbles with 

 Cretaceous fossils. In this region these basement rocks are so dissected 

 that their remains constitute many of the islands of the Virgin group. 



But in Antigua and Grande Terre of Guadeloupe the strata overly- 

 ing the denuded igneous basement is a subaqueous redistributed tuff 

 with some calcareous beds in the upper zone, over which rest conform- 

 ably the white limestones, a marly deposit containing Oligocene corals 

 and shells.^ South of the Guadeloupe Archipelago and Monserrat, 

 the outer islands disappear, and the writer is not aware of the occur- 

 rence of the early Tertiary limestones remaining so as to leave evidence 

 of the age of the igneous basement, though by its lithological character- 

 istics and the physical features of its ancient surface one can hardly be 

 far astray in concluding that they are of the same age as the similar 

 formations on the islands to the north. In Barbadoes the Oligocene 

 limestones reappear, but here there are no igneous deposits. It thus 

 seems that the whole Caribbean plateau beneath both the volcanic 

 ridges and the limestone islands is underlaid by an igneous formation 

 dating back to the commencement of the Tertiary periods at least, if 

 indeed these rocks are not as old as those of St. Croix, that is, as 

 ancient as the Cretaceous period. 



In St. Martin, St. Bartholomew, and Antigua the mountain belts 

 are entirely made up of the denuded rocks of this old igneous forma- 

 tion without a covering mantle. So also, part of Statia, St. Kitts, 

 Monserrat, the southern end of Martinique, portions of St. Lucia, and 

 the southern end of St. Vincent have their surfaces molded out of the 

 ancient igneous accumulations ; but elsewhere in these islands, as also 



^"On the Geology of the Northeastern West India Islands," Trans. Roy. Swed- 

 ish Acad. Sc, Vol. IX,, 1870-71. 



^See "Geological and Physical Development of the Various Windward Islands," 

 six papers by J. W. Spencer, in Quar. Jour. Geol. Soc. Lond., Vol. LVII (1901), 

 pp. 409-543, and Vol. LVIII (1902), pp. 341-65. 



