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ANNALS NEW YORK ACADEMY OF SCIENCES 



Zilla because their taxonomy is too unsatisfactoiT. Drassiis has been 

 split lip by authors but even one of its parts is practically cosmopolitan. 

 Tetragnatlia, Tegenaria and Philodromus are cosmopolitan, even includ- 

 ing frigid regions. Clubiona is found throughout most of the temperate 

 and tropical regions ; Nephila and Sprassus are cosmotropical ; and Thom- 

 isus is found throughout most of the continental, at least, Old World. 

 Certain points in the ranges of the other seven genera are shown in figure 

 G, only those most distant from the Baltic together with several inter- 

 mediate stations being indicated. The supposition that all these seven 



Fig. 7. — Distribution of SegestriincB 

 Lines refer to Ser/estria and dots to Ariadna. 



genera originated in the Baltic region in, sa}', the Eocene would be ab- 

 surd, but supposing that they did, would not the several million years 

 since then, including as they do a long space of mild or tropical condi- 

 tions in the Arctic, have been sufficient for the dispersal of these genera 

 more or less along the lines indicated in the figure? I feel that even 

 the rather well authenticated land connections in the jSTorth Polar region 

 would not be necessary, for we must remember that the distances are 

 much shorter in the polar regions than they appear to be on a Mercator^s 

 projection. Certainly, there seems to be no need for Antarctic connec- 

 tions. The distribution of Archcea has already been mentioned. The 

 onl}^ other genus of special note is Segestria. The discontinuity of its 



