NO. 2226. DISTRIBUTION OF ENTOMOSTRACA—DODDS. 87 



lowlands, and rises as an island, surrounded by faunas of warmer 

 climates. This difference of situation does not, however, make any- 

 apparent or significant difference in the nature of the two faunas. 

 The conditions and fauna in both cases, as pointed out by Zschokke, 

 are glacial in their nature — in the Alps as a remnant left at the 

 retreat of the glacier, and in the Rockies as a direct southern exten- 

 sion of present glacial conditions in the north. 



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