586 PROCEEDINGS OF THE ACADEMY OF [NoV., 



of St. John's Harbor and north to Corbizon Point. The land shells 

 now living in the island were collected (when encountered) for 

 comparison with the faunas of neighboring islands, but this collection 

 is probably not complete. Upon the field notes and observations 

 on the geology the following description of the geology of Antigua 

 is based. 



The first notice of the geology of the island of Antigua appeared 

 in 1819 as a preliminary paper in the American Journal of Science,^ 

 by Dr. Nicholas Nugent, of Antigua, but this was followed two 

 years later by a fuller paper by Dr. Nugent, entitled, ''A Sketch of the 

 Geology of the Island of Antigua, "^ published in the Transactions 

 of the Geological Society of London. 



Dr. Nugent's paper was communicated to the 'Geological Society 

 on November 5, 1819, and was accompanied by a collection of rocks 

 and fossils to illustrate the paper; of which collection the fossil corals 

 have been studied about forty years after their presentation by 

 P. Martin Duncan. The moUusks have never been worked over and 

 a list of the species published. Later, in 1839, Professor S. Hovey, 

 of Yale and Amherst Colleges, visited the island, and with Dr. Nugent 

 as guide, examined some of the principal localities. Upon his return 

 to America he published a paper ^ on the ''Geology of Antigua," 

 compiled, as he himself states in this communication, frmn Nugent's 

 "Sketch" and from a paper by Dr. Thomas Nicholson, written 

 for the Antigua Almanac and Register. Dr. Nugent divides the 

 geological formations of the island into four, of which the basal 

 member. No. 1, is described as "trap and trap-breccia," No. 2 is 

 "stratified conglomerate," No. 3 is "chert," and No. 4 is "marl 

 or calcareous rock. " In his maps he reverses the order of the " strati- 

 fied conglomerate" and the "chert," but explains in the Appendix'^ 

 that this was a mistake, although he at one time entertained this 

 view of the structure of the island. Dr. Nugent's paper, which shows 

 keen observation, remained for long the classic on Antiguan geology, 

 until the appearance of M. J. C. Purves's Geological Sketch of the 



1 Am. Jour. Sci., ser. 1, Vol. I (1819), p. 140. Wm. Maclure refers to the 

 island of Antigua in his "Observations on the Geology of the West Indian Islands, 

 from Barbadoes to Santa Cruz, " but he did not visit the island. See Jturnal 

 Acad. Nat. Sci. Philadelphia, Vol. I, pt. 1, 1817. 



2 Trans. Geol. Soc. ser. 1, Vol. V (1821), pp. 459-475. 



^ "Geology of Antigua, " by Prof. S. Hovey, Amer. Jour. Sci., ser. 1, Vol. XXXV 

 (1839), pp. 75-85. 



* Extracts from a letter to Professor William Buckland, one of the Vice- 

 presidents of the Geological Society of London, from Dr. Nugent. Trans. Geol. 

 Soc, series 1, Vol. V (1821), p. 470. 



