CRUSTACEA. I53 



of our east-coast species, reaching sometimes a length of two inches, but is 

 exceeded by an allied form from the deep seas which is eleven inches long. 

 More distantly related are the peculiar 'whale-lice,' which occur on the 

 skin of the larger whales, sometimes in enormous quantities. They are 

 strikingly like a spider in appearance, and are among the most aberrant of 

 the Crustacea. 



