PEEFAOE 



The ambition of this volume is that it shall be one to 

 which beginners in the subject will naturally have re- 

 course, and one which experienced observers may willingly 

 keep at hand for refreshment of the memory and ready 

 reference. An attempt has been made in it to bring the 

 reader face to face with the vastness of the theme, to show 

 him how variously it may engage the human mind, and 

 to give him a groundwork of information as to the objects 

 to be examined, with a side glance at the literature that 

 has discussed them. 



It is not very generally known that the species of 

 Crustacea extend to a number of several thousands, and 

 that some of these species people parts of the ocean in 

 enormous swarms. Of some of the groups the genei'al 

 character is familiar to every one, but there are also 

 groups of which most persons either know nothing or 

 have not the least idea that they belong to the Crustacea. 

 The beginner, therefore, will have provinces of a new 

 world opened to his exploration. There is curiosity to 

 be gratified. The sporting instinct will discover many 

 an unexhausted territory. In the manners and customs 



