CHAPTER VI 



GEOGRAPHIC DISTRIBUTION 



There are many papers on the Recent foraminifera but nearly 

 all of these are faunal papers taking up limited areas. In the 

 case of the Challenger Report which covered all the seas, Brady 

 had such a wide latitude in his conception of species that faunal 

 limits were not distinguished except in a general way. It has 

 been possible in the studies of all the living species of certain 

 genera as well as a study of faunas from various parts of the 

 world to arrive at a fairly comprehensive idea of the living 

 foraminiferal fauna. That there are very definite faunas is 

 apparent and many of them may be subdivided. These faunas 

 are of interest to the worker on fossil foraminifera as well as 

 to one working on the living faunas, for the later Tertiary and 

 Recent faunas have been established for a considerable period. 

 The Pliocene faunas of Florida and California are very dis- 

 similar but each is very close to the Recent fauna now living 

 off the coast of the respective regions. 



The migrations of faunas in Tertiary times have been marked. 

 For example the Eocene (Lutetian) fauna of southern England 

 and the Paris Basin migrated gradually through the Mediter- 

 ranean region to Australia. Many of these species of the 

 European Eocene are found but little changed in the Miocene of 

 Australia and some of them are found with but little modifica- 

 tion in the recent material from the Australian coast. The 

 Miocene warm water faunas of the Austrian and Hungarian 

 regions also migrated to the Indo-Pacific, and many of the 

 species are still living in that area. So in the Lower Oligocene 

 of the Southeastern United States, the species became extinct 

 at the end of the Lower Oligocene in that region but had 

 migrated to the Pacific, and now some of them or closely allied 

 species still persist. Many of the large forms now living only 

 in the Indo-Pacific, Operculina, Siderolites, Baculogypsina, Cal- 



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