CLAMS, OYSTERS, AND MUSSELS 



119 



used as a means of defense. When pursued by an enemy, 

 the squid ejects some of this pigment which colors the 

 water and blinds the 

 pursuer. 



The body of the 

 giant squi( 1 soirietimes 

 becomes eight or nine 

 feet long, while the 

 largest pair of arms 

 may attain a length 

 of twenty or thirty 

 feet. 



Cuttlefish.— The in- 

 ternal shell of this 

 animal is calcareous 

 an( I furnishes the 

 cuttle bone so uni- 

 versally used for f ceil- 

 ing canaries. The 

 bofly of a cuttlefish 

 is much shorter and 

 more oval than the 

 squid's. Otherwise 

 these two rnollusks 

 are much alike. It 

 is from the cuttlefisli. 



S<iuid. 



Sepia, that the pigment is obtained from which sepia ink 

 is mafle. See Figure 66. 



Octopus. — The body of the octopus is more or less egg- 

 shaped, and usually not large. A species on the Pacific 

 coast is sometimes found with a body one foot long, six" 

 inches in diameter, and with arms twelve to fourteen feet 



