1866.] GUPPY WEST-INDIAN TERTIARIES. 585 



common to the Miocene of the West Indies and that of North 

 America, but that those types which give a distinctive character to 

 the fauna of the Caribean Miocene, and which assimilate it to that 

 of Europe, were absent from the JSTorth American province. When 

 to this is added the likeness of the Miocene faunas of the West 

 Indies and of Europe to that now existing in the east, it becomes 

 a matter of high interest to explain the causes of that simi- 

 larity, especially as it has been urged of late that a similarity of 

 organic contents implies a want of contemporaneity in the contain- 

 ing deposits when separated by a considerable interval in space. 

 Such explanation may possibly be found in the former distribution 

 of land and water allowing or preventing the free migration of 

 organic beings. 



Respecting the Atlantis hypothesis, it is unnecessary to suppose 

 that the Atlantis existed as a continent up to the close of the Miocene 

 period. It appears just as easy to account for the facts by suppo- 

 sing the existence of such a connexion antecedently to the Miocene 

 period* ; for, as far as regards the Swiss flora, Heer does not consider 

 any of the species to be identical with living or fossil American forms. 

 If they are merely closely allied species, they may have been derived 

 from common ancestors in the Eocene period, or, at any rate, in the 

 beginning of the Miocene. Our views on this point must partly 

 depend on the longevity of vegetable species as compared with those 

 of Mollusca ; but, as bearing on the subject, we have the testimony 

 of Lesquereux and Newberry that the Eocene plants of America are 

 closely related to those of the Miocene of Europe, as well as to 'the 

 recent flora of the former country f ; and American geologists seem 

 to entertain no doubt as to the Eocene age of these remains, the 

 deposits in which they are imbedded having been proved to pass 

 under the Claiborne (Eocene) beds. 



I see, then, some ground for adhering to the views entertained by 

 Eorbes and God win- Austen, concurred in by Darwin, and supported 

 by Dr. Duncan's investigations, that Europe was probably during 

 the Miocene period, much in the condition of the present Pacific 

 Ocean, and that, as observed by the latter palaeontologist, it is 

 reasonable to infer the prolongation of the maze of islands across 

 the Atlantic. The Mollusca of the Caribean Miocene generally 

 betoken a clear sea, and probably lived on the slopes of coral-banks. 

 As confirmatory of this view, I may cite the absence of littoral shells 

 from the Caribean Miocene fauna. 



When the climate of Europe became inimical to the existence of 

 those species which were adapted only to a high temperature, they 

 would migrate or become extinct ; and supposing that the Atlantis 

 had in the meantime become broken up and submerged, their migra- 

 tion would take place towards the east, presuming that there was a 

 sea-passage in that direction, which seems to be generally considered 



* Vide Intellectual Observer, No. ivi. pp. 88-97. Mr. Jenkins informs me 

 that his paper was written in ignorance of the coincidence in the views we enter- 

 tain on this svibject, and without a knowledge of the contents of this paper, 



t Dana, ' Manual of Geology,' p. 513. 



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