CEPHALOPODS. 77 
The animal holds on to the sides of its shell by the so-called 
''sails" or broad thin ends of two of its arms, which se- 
crete the shell. 
Fig. 93.— Giant Squid, reduced in size. After Verrill. From Emerton. 
Literature. — Article Mollusca, by E. R. Lankester, in Encyclo- 
psedia Britannica. Woodward's Manual of the Molliisca, 1868. 
