CONTRIBUTION TO THE PALEONTOLOGY OF TRINIDAD. 35 



■ 



presumably carried by oceanic currents corresponding to the present Gulf Stream 

 eastward; but the spread of the other genera cannot thus be accounted for. 

 Possibly we have in these instances cases of parallelisms of development. 





Recent and 

 Quaternary. 



South America. 

 Molluscan fauna northward 



from the La Plata. 



Oligocene 



North America. 

 Molluscan fauna southward 

 from Cape Hatteras. 



Eocene* 



Cretaceous 



Upper Oligocene faunas of Cumana, 



Trinidad, Jamaica. 



Lower Oligocene faunas of San Fernando 



and Manzanilla, Trinidad* 



Lignitic fauna of Soldado Rock, Gulf of 



Pari a. 



Midway fauna of Soldado Rock and 



Pernambuco. 



Upper Oligocene of Florida. (Tampa silex 



beds, Chipola marls.) 



Lower Oligocene of Vicksburg, Mississippi. 



Lignit 



States, 



Midway fauna of Alabama and other Gulf 

 States. 



Carbonifer- 

 ous. 



Cretaceous faunas of Venezuela and 



Colombia. 



Faunas of the Amazonian Valley in 



BraziJ, Bolivia and Peru. 



Devonian. 



Silurian. 



Erer6 formation, Brazil. 

 Maecuru beds, Brazil. 



Cretaceous of the southwestern United 



States and Mexico. 



Coal meaaures of the western United States. 



(More than half the species being 

 identical.) 



Onondaga of the United States. 

 Oriskany of Alabama, etc. 



Brazilian and Venezuelan Silurian faunas [Niagaran of the United States 



(Upper formation). 



Brazilian Silurian faunas (Lower forma- 1 Clinton and Richmond of the United States, 

 tion). 



As above noted, the Oligocene faunas of Cumana, Trinidad, and the Antilles 

 in general, show close resemblances to the recent fauna of the west coasts of 

 Central America and of northwestern South America- This is due to the pre- 

 Oligocene free waterway over the Isthmus from the Caribbean to the Pacific. 



Regarding the resemblances of the Trinidad and other Antillean Oligocene to 

 that of southern France, the writer's observations of Tertiary forms in general 



are the same 



those of M. Douvill6 for the South American Cretaceous 



namely, that although the European and American formations include a very 



few species in common and have a certain 

 distinct. 7 



de famille, their evolution was 



Studies by Drs. Dall and Verrill of the living molluscan and coral faunas of 

 Florida and the West Indies indicate that the present faunas on the shores of the 

 Gulf Coast of the United States came originally from the coast of Brazil And, as 

 Dr. Branner has already suggested, it seems very probable that the Tertiary 

 faunas of the Gulf States may have also originated on the Brazilian and Antillean 

 shores. The Soldado Eocene fauna is a strong argument in favor of this hy- 

 pothesis. 



7 



Ann. de la Soc. Royale Zoologique et Malacologique de Belgique, t. XLI, pp. 142-155, 1906 



