458 NATURAL HISTORY. 



Division II. INVERTEBRATA. (Lat, without vertebra.) 



Class VI. . . MOLLUSCA. (Lat. from mollis, soft ; properly, a soft 



nut.) 



Order. . . . CEPHALOPODA. (Gr. Ke^a^, the head ; 7rcwf,afoot.) 

 Family . . . Octopidae. (Gr. 'Orw, eight; Trot'f, a foot.) 



Vulgaris (Lat. common), the Cuttle-fish. 



The Mollusca have neither spine nor bones, the nervous sys- 

 tem consisting of a number of nervous knobs called*' ganglia," 

 which give off filamentous nerves in different directions. 



Few Molluscs possess eyes, but in one or two, as the snails 

 and slugs, those organs are to be found, and in the higher 

 Molluscs, such as the Cuttle-fish, we see not only large and 

 brilliant eyes, but also organs of hearing. 



The Cephalopoda, so called by the organs of movement sur- 

 rounding the head, are divided into naked and testaceous* or 

 covered with a shell. 



The COMMON CUTTLE-FISH is an example of a naked cephal- 

 opodous mollusc. This repulsive looking creature is common on 

 our shores, and is, in spite of its unpleasant appearance, often 



* Derived from Lat. testa, a shell. 



