THE CEPHALOPODA 341 
- Stoloteuthis, Verrill, and Inioteuthis, Verrill, have no internal shell. 
Heteroteuthis, Gray. Huprymna, Steenstrup. Famity 3. IDIOSEPIIDAE. 
Steenstrup. Body elongated, with rudimentary terminal fins. Internal 
shell almost lost. Genus—Jdiosepius, Steenstrup ; this tiny Cephalopod 
is only 14 centimetre long, and has a mucous pore at the aboral 
Fig. 299. 
Sepia officinalis, dorsal view of a dead specimen, with the short arms spread out and the long 
arms pulled out of their sacs. a, neck; b, lateral fins ; ¢, 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. Famtty 4. 
SEPIADARIIDAE, Steenstrup. Body short; the mantle fused to the head 
anteriorly (dorsally). No shell. Genera—sSepiadariwm, Steenstrup ; fins 
short, situated at the aboral extremity of the body ; from the Pacific Ocean. 
Sepioloidea, d’Orbigny ; fins nearly as long as the body; Australian. Famity 
5, LoLIGINIDAE, Leach. Body elongated and conical ; fins triangular or 
