RECENT FRESHWATER INVESTIGATIONS 317 



deserves prominent notice. Valuable articles on the group 

 are Mnizek, Marsh (95), E. B. Forbes, Schacht and Brewer 

 On the Cladocera the revision of Richard (94, 96) is a model 

 of completeness and accuracy. Birge (93, 94), Ross (96), 

 Turner (93) in this country, and Stenroos (95, 97), Stingelin 

 (95), Weltner (96) in Europe, have contributed to a study of 

 the same group. On all of the plankton crustaceans much 

 emphasis has been laid and in most of the articles noted 

 under the head of distribution may be found important tax- 

 onomic notes on these groups. 



The distribution of freshwater life may be regarded from 

 the standpoint of the single body of water or through a com- 

 parative view of different bodies of water. In the latter case 

 one may consider those bodies which are within a given geo- 

 graphic area, or those which are associated in character. Ac- 

 cordingly it is permissible to speak of the geographic, the hydro- 

 graphic and the areal distribution of freshwater organisms. In 

 considering first the geographic distribution of freshwater ani- 

 mals, regions are designated by ordinary geographic terms since 

 a basis for subdivisions into faunal regions has not yet been 

 worked out save in Russia by Zograf. Of general value on 

 the geographic distribution of freshwater animals is the work 

 of Schewiakoff (93a) on the Protozoa which seems to indicate a 

 cosmopolitan distribution for these forms. Frenzel (97b) 

 doubts this on the basis of studies in South America, since of 

 88 species found in Argentina, 44 are new. The accuracy of 

 these studies has, however, been questioned. 



Observations on Australian forms are reported by Chilton 

 and Sars, from the Pacific Islands (Samoa) by Kramer, from 

 Sumatra by Richard (94c) and from Ceylon by Poppe (95b) and 

 Daday (98). From eastern Asia Richard (94b) is the only 

 record of the freshwater fauna noted. From Asia Minor 

 Barrois (94) and Richard (95, 96c) complete the list. 



Northern Africa is touched upon in Barrois (93) and Rich- 

 ard (93). German East Africa has a well planned biological 

 survey of governmental character in progress. Reports touch- 



