v i CONTENTS. 



Page 



Table showing the Geographical Distribution* of every Species of Camba- 



rus and astacus 15' 



Table showing oce Present Knowledge of the Distribution of the North 

 American Species of Cambakus and Astacus, arranged according to 

 States and Territories ......••■•• 10° 



Distribution of the North American Species of Cambaeus and Astacus 



according to Kivek Systems 1*3 



General Conclusions derived from the Facts known concerning the Geo- 

 graphical Distribution of the Astacid^: 175 



Index to the Species 1S1 



Explanation of the Plates ........... 183 



