172 Puget Sound Marine Sta. Pub. Vol. 1, No. 14 



sufficient to justify further investigation of the subject and to call into 

 question the validity of conclusions as to the uniform character of animals 

 living under obviously different conditions. 



The Department of Zoology at the University of Illinois supplied 

 the map and bore part of the expense of the preparation of the paper 

 for the press. The expense of the investigation was borne by the Puget 

 Sound Marine Station. 



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