CRUSTACEANS— MOLLUSCS 



183 



A 



Fig. 128. — Phyllosoma. (After Fig. 129. — Sergestes Larva.* 

 Gardiner.) (After Claus.) 



/^% 



Fig. 130. — .Lucifer. (After Claus.) 



The cuttle-fishes, of which the octopus and squid are 

 too well-known to require a figure, are all more or less 

 planktonic, although many, especially in shallow water, 

 are bottom feeders; they sometimes attain a huge size. 

 Some have a web between the arms, which thus form 

 a great funnel. Any forms with an external shell 

 (except the familiar Pearly Nautilus and Argonauta) 

 should be carefully preserved for study by experts, 

 such as the body of the little Spirula, the dead shells 

 of which are not uncommon in Eastern seas. 



* The right side of this figure is of the dorsal or upper 

 surface ; on the left side is drawn the ventral or under surface 

 to show the limbs. 



