vi CONTENTS. 



PAGE 



TABLE SHOWING THE GEOGRAPHICAL DISTRIBUTION OF EVEKY SPECIES OF CAMBA- 



EUS AND ASTACUS . . ...... 157 



TABLE SHOWING OUR PRESENT KNOWLEDGE OF THE DISTRIBUTION OF THE NORTH 

 AMERICAN SPECIES OF CAMBARUS AND ASTACUS, ARRANGED ACCORDING TO 

 STATES AND TERRITORIES 105 



DISTRIBUTION OF THE NORTH AMERICAN SPECIES OF CAMBARUS AND ASTACUS 



ACCORDING TO RlVER SYSTEMS 173 



GENERAL CONCLUSIONS DERIVED FKOM THE FACTS KNOWN CONCERNING THE GEO- 

 GRAPHICAL DISTRIBUTION OF THE ASTACID^E 175 



INDEX TO THE SPECIES . . . 181 



EXPLANATION OF THE PLATES 183 



