GEOLOGY. 359 



(3) a variety of igneous rocks which have been intruded into or extruded 

 over (2) ; (4) Pleistocene non-marine marls. 



The geologic succession in St. Bartholomew and St. Martin is litho- 

 logically similar to that in Antigua, but it appears that the limestone in 

 each of the three islands is different in age. Anguilla is mostly com- 

 posed of fossiliferous marl and limestone, which is underlain by igneous 

 rock. The limestone in Anguilla may be of the same age as that in St. 

 Martin. Extensive collections were made in Antigua, St. Bartholo- 

 mew, and Anguilla, and a small collection was obtained in St. Martin. 

 An attempt was made to procure representatives of the entire biologic 

 assemblage in each formation. The collections from the marine beds, 

 therefore, include calcareous algae, foraminifera, corals, echinoids, 

 mollusks, brachiopods, and a few Crustacea. The collections have 

 already had the requisite preliminary preparatory work done on them, 

 and the fossils have been separated and segregated according to the 

 respective groups, and distributed to specialists for study. 



A few general statements may be made regarding the probable 

 geologic age of each of the respective fossiliferous deposits. The lime- 

 stone and interbedded, stratified tuffs, etc., of St. Bartholomew have 

 been referred to the Eocene by Professor P. T. Cleve. These seem to 

 be the oldest of the sediments studied. They contain one species of 

 coral, Stylocoenia duerdeni Vaughan, which also occurs in the Richmond 

 beds of Jamaica. A peculiar fungid genus of corals, to which I have 

 given the name Antilloseris, is one of the commonest in St. Bartholo- 

 mew and is a characteristic fossil of the Cambridge beds of Jamaica. 

 Hill refers both the Richmond and the Cambridge beds to the Eocene. 

 Certain foraminifera, a species of Orbitoides found abundantly in St. 

 Bartholomew were collected in beds of reputed Eocene age in Cuba, 

 and a similar species is found interbedded with the Bohio conglomerate 

 in Panama. Another species of Orbitoides, a large, stellate form, is 

 similar to one which occurs in beds referred to the Vicksburg formation 

 at Marianna, Florida, and near Bainbridge, Georgia. A large species 

 of Cerithium from St. Bartholomew suggests an Eocene age. As some 

 of the Orbitoides suggest lower Ohgocene as the age, and as some other 

 fossils suggest upper Eocene as the age, the inference seems safe that the 

 horizon is one or the other. As the discrimination between upper Eocene 

 and lower Oligocene in the southeastern United States is not positive, 

 this correlation is fairly definite. The fossils indicate the possibility of 

 correlations between the southeastern United States, Cuba, St. Bartholo- 

 mew, Trinidad, Panama, and perhaps other areas in Central America. 



The next younger fauna is the Antiguan. In 1900 1 published a note 

 in Science correlating the coral-reef horizon at the base of the Chatta- 

 hoochee formation and immediately overlying the Ocala horizon of the 

 Vicksburg formation near Bainbridge, Georgia, with the Antiguan 

 coral-reef beds. This correlation was based on the similarity in facies 



