X CONTENTS. 



CHAPTER V. 



PAGE 



The Comparative Morphology of the Crayfish. The struc- 

 ture AND THE development OF THE CrAYFISH COMPARED 

 WITH THOSE OF OTHER LIVING BEINGS 227 



CHAPTELl VI. 



The Distribution and the ^Etiology of the Crayfishes . . 288 



NOTES ' . . 347 



BIBLIOGRAPIiy 357 



INDEX 363 



