The Spine-finned Teleostei 401 



groups. These bridges were the S. and N. Atlantis land- 

 masses, the former of w^iich connected the Central S. 

 American with the West African coast, the latter the N. E. 

 North American with the South European coast; also the 

 Indo-Mascarene bridge that more or less connected Mada- 

 gascar and S. E. Africa with India. A mid or late Cretace- 

 ous connection seems also to have united the East Indies 

 with Australia. 



Along these land-bridges with their freshwater passage- 

 ways, the Centrarchidae and Percidae, along with deriva- 

 tive Cichlid and Serranid families, migrated eastward Into 

 and across Africa till the East Indies and even Australia 

 were reached. Derivative marine genera and families 

 passed off from some of these, or from the Berycidae, and 

 established ever wider geographic connections in the bays, 

 seas and oceans. 



A less striking migration across the Amerlco-European 

 or North Atlantis bridge was also effected, contemporane- 

 ously with active migration in both directions of salmonid, 

 cyprlnid, silurid, esocid and gastrosteld families and genera. 



From Oligocene on to late Miocene times the bridges 

 were completely destroyed, and continued evolution of the 

 above took place most actively over marine areas that 

 were widely connected; while evolution of species and 

 genera — rarely larger groups — proceeded in the freshwater 

 centres or passageways that were left, after destruction of 

 the connecting bridges, and rearrangement of the remaining 

 continental masses, had been effected. 



