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MANUAL OF ZOOLOGY. 



SECTION B. DECAPODA. The Cephalopods of this section 

 have eight arms and two additional "tentacles," which are 

 much longer than the true arms, are retractile, and have ex- 

 panded, club-shaped extremities (fig. 231). The suckers are 



D 



Fig. 231. A, The common Calamary (Loligo vulgaris), reduced in size : a One of the 

 ordinary arms ; / One of the longer arms or tentacles." B, Skeleton or " pen" of 

 the same, one-fourth natural size (after Woodward). C, Side view of one of the 

 suckers, showing the horny hooks surrounding the margin. D, View of the head 

 from in front, showing the bases of the arms (a) and tentacles (t), the mouth (/), 

 and the funnel (./). 



pedunculated ; the body is always provided with lateral fins, 

 and the shell is always internal. 



This section comprises the three living families of the 



