B. «T. L. GUPPY ON THE MIOCENE FOSSILS OF HAITI. 517 



was from the January (1875) number of the ' Journal de Conchylio- 

 logie,' which, however. I did not receive until some time after the 

 date of its publication. In August last Prof. Gabb did me the 

 kindness to send me a copy of his publications relating to the 

 geology and palceontology of Haiti. I deemed the opportunity a 

 favourable one for reexamining the Haitian fossil mollusca, which 

 had been untouched since 1853. The present communication, 

 which embodies the results of my reexamination, is confined for 

 the most part to such species as I have identified in the collection 

 of the Geological Society, or have noticed in other collections of 

 West-Indian Tertiary fossils. 



We have not escaped the tendency, almost inevitable in the case 

 of little-known forms, to describe mere varieties, some more or less 

 permanent, some merely individual, under distinct specific names. 

 Prof. Gabb has done good service by uniting together some of these 

 artificially separated forms ; and in this labour he has had the 

 advantage of large suites of specimens collected by himself in Haiti. 

 While contributing my quota towards a reduction of our superfluous 

 nomenclature, I may observe that it is not always a disadvantage in 

 the beginning (particularly when the descriptions are accompanied 

 by good figures) to distinguish the various forms which are mis- 

 taken for distinct species. Owing apparently to the great exube- 

 rance of Molluscan life in the "West-Indian Miocene, much variation 

 occurred, especially in certain genera. 



In all the corrections I have ventured on in respect of Prof. 

 Gabb's determinations, I have not acted in any spirit of derogation of 

 his work, which I consider very valuable j and I could congratulate 

 myself if my own had been at all times as well done. 



One of the results stated by Mr. Carrick Moore has been brought 

 out more strongly by Prof. Gabb's examination of the Haitian 

 fossils. It is the alliance of the West-Indian Miocene fauna to that 

 of the west coast of South America; and I think now that the 

 conviction can hardly be resisted that during some portion of the 

 Miocene period there was a free communication between the Pacific 

 and the Atlantic. Put other alliances point to the west coast of 

 Africa ; and there remain other alliances still more close with the 

 Eastern and Indian Seas. 



In a letter to me, dated 18th September, 1871, the late Prof. 

 William Stimpson informed me that in the deep-sea explorations 

 off Florida he had discovered shells either identical with or very 

 closely allied to some species of the West-Indian Miocene. Among 

 them he cited Conusplaiuliratus,Pleurotoma Barrctti ( = P1. liaitensis), 

 Phos elegans, and Corbula viral aea. 



Por the sake of conciseness I have, in the following remarks, used 

 the abbreviation G. J. for the Quarterly Journal of the Geological 

 Society. 



1. Dextaltot dissemile, Guppv, G. J. vol. xxii. p. 292, pi. xvii. 

 fig. 4. 

 I am inclined to believe that GabVs D. ponderosum is a form of 



