THE CEPHALOPODA 



34i 



Stoloteuthis, Verrill, and Inioteuthis, Verrill, have no internal shell. 

 Heteroteuthis, Gray. Euprymna, Steenstrup. FAMILY 3. IDIOSEPIIDAE. 

 Steenstrup. Body elongated, with rudimentary terminal fins. Internal 

 shell almost lost. Genus Idiosepius, Steenstrup. ; this tiny Cephalopod 

 is only Ij centimetre long, and has a mucous pore at the aboral 



Fio. 299. 



Sepia riffldnalis, dorsal view of a dead specimen, with the short arms spread out and the long 

 arms pulled out of their sacs, o, neck ; 6, lateral tins ; c, the eight shorter arms ; d, the two 

 long tentacular arms ; e, the eyes. (From Lankester, after Owen.) 



extremity of the body ; it inhabits the Indian Ocean. FAMILY 4. 

 SEPIADARIIDAE, Steenstrup. Body short ; the mantle fused to the head 

 anteriorly (dorsally). No shell. Genera Sepiadarium, Steenstrup ; tins 

 short, situated at the aboral extremity of the body ; from the Pacific Ocean. 

 Sepioloidea, d'Orbigny ; fins nearly as long as the body ; Australian. FAMILY 

 5. LOLIGINIDAE, Leach. Body elongated and conical ; fins triangular or 



