14 PEOCEEDINGS OV THE GEOLOGICAL SOCIETY. [NoV. 9, 



tude should be unrepresented in the larger islands. The character- 

 istic corals of the Eocene strata of the Southern States are not 

 amongst those from Port Maria. 



The corals obtained from Yere, Bowden, and ISTavy Island, off 

 Port Antonio, have no general resemblance to those from the Eocene 

 and Cretaceous strata, but present the appearance of the common 

 specimens of the various Miocene shales and marls of San Domingo 

 and the European Miocene ; and all are absent from the existing 

 coral-fauna of the West Indies. The new species of Flabelhmi is 

 unlike that of the Nivaje shale, and its genus is unknown in the 

 Caribbean Sea. The existence of the genus in every other coral- 

 sea, and its discovery in the Miocene of the Antilles, have already 

 been noticed in a former communication. The genus Flacotrochus 

 is represented by a second species in the Jamaican Miocene ; it has 

 no species in the Caribbean Sea, but several occur in Oceania ; and its 

 fossil species are found in the Australian* and San-Domingan Ter- 

 tiaries. The Placotrochus costatus is a very interesting form, for it is 

 mimetic of the new species of Flabellum just mentioned. Pkico- 

 trochus differs from Flabellum in having a lamellar columella ; but 

 the genera are closely alhed, and their habits are very much alike : 

 it happens, moreover, that several sets of species resemble each other, 

 except in the prominent generic peculiarity, and are mimetic. 



The Placocyathus which I have ventured to name after Mr. Carrick 

 Moore is allied to P. Barretti, nobis ; and the new TJiysanus adds 

 another species to that beautiful genus. 



The comparative absence of compound corals from the Jamaican 

 Miocene is very remarkable ; and equally interesting, in reference to 

 the deep-sea nature of a part of the coral-fauna, is the abundance of 

 Foraminifera, which crowd amongst and fill up the interstices of the 

 specimens. The reef-coral AlveoiDora, however, exists in the "White 

 Limestone, and there is, therefore, a proof of some variation in the 

 depth of the sea during the deposition of the Jamaican Miocene. 



The general correlation of the Jamaican Mid-tertiary marls, sands, 

 and limestones with the Nivaje and Esperanza shales and the lime- 

 stone of San Domingo has been noticed in a former communication. 

 These Miocene deposits are the equivalent formations to the Newer 

 Parian of Trinidad and the mainland, to the three sets of strata in 

 Antigua, and to the calcareous bed of Barbuda, (feet; their coral- 

 faunae have much in common, and bear but slight affinity to that 

 existing in the Caribbean Sea, but a well-marked resemblance to 

 the Australian, Oceanian, and East Indian coral-fauna ; moreover, 

 they are closely related by identity of species with the fauna of the 

 Paluns, of the Turin Miocene, of the Yienna basin, and of the lowest 

 Maltese limestone. 



* P. M. Duncan, Ann. & Mag. Nat. Hist. vol. xiv. 1864, p. 161. 

 t The small island off Port Antonio contains a Pteropod-marl, according 

 to the late Mr. Barrett, and the Trocliocyathus obesus was derived from it. 



