A PROCEEDINGS OF THE NATIONAL MUSEUM vol. 77 



cases, usually with a study of topotype material at the same time. 

 We have been exceptionally fortunate in having abundant material 

 from nearly all the important type localities of Europe and elsewhere, 

 so that the species that we have actually seen from their type localities 

 represent a large part of the total number. Many persons and insti- 

 tutions have supplied us with material, and all can not be thanked 

 individually. We have ourselves collected at many of the type locali- 

 ties. In Vienna, for example, Ozawa washed down more than a 

 quarter of a ton of clays from the type localities of Baden and Nuss- 

 dorf, with the result that we have had for study beautiful suites of 

 specimens of species from these important localities. Of the localities 

 of England, France, Italy, Spain, Belgium, HoUand, Germany, Aus- 

 tria, Hungary, etc., we have also had abundant material. From 

 Japan, Australia, Fiji, New Guinea, etc., material has been abun- 

 dantly supplied as well as from northern South Amerca, Trinidad, 

 Mexico, and the United States. Altogether we have studied material 

 probably from more than a thousand localities, and the number of 

 mounted specimens totals many thousands. We have had for study 

 therefore an exceptional collection, and the results of our study, 

 while not in any sense final, will nevertheless have the satisfaction of 

 being based on abundant material from type localities. 



DISTRIBUTION 



In the present work it has been found useless to try to check up the 

 distribution of species from the published records. So many of the 

 species have been wrongly used and so many of the records are unac- 

 companied by figures that the resulting confusion can only be 

 straightened out by an actual study of the existing collections on which 

 these records were based. Such a study at this time is impossible. 

 For these reasons we have used the specimens available to us and the 

 notes made in studies of European collections. 



Even with the many thousands of mounted specimens of Poly- 

 morphinidae that we have, it will be found that the ranges both 

 geographically and geologically are probably not entirely correct for 

 some of the species. The distribution of species as we have identified 

 them was plotted in colors on a world map so that the distribution of 

 each species as we have identified it might be quickly seen. 



The maps show one thing in particular that was already apparent 

 from our study of many specimens; that is, that smooth, rather primi- 

 tive species such as Globulina gibba and Guttulina problema have a very 

 long geologic history and are widely distributed. On the other hand, 

 a similar study of the maps of the species of Polymorphina shows that 

 they are each restricted to narrow limits both in present oceans and in 

 the fossil series. In the latter, we are dealing with species of a genus 

 that is specialized and has developed most of its species in the late 



