432 A. E. Verrill — North American Cephalopods. 



follicular glands; liver small, far forward; ink-sac small. Pen slen- 

 der anteriorly, as long as the mantle. Hectocotylized arm not 

 observed. All the arms bear suckers. 



Family DESMOTEUTHID^ Yerrill. (See p. 300). 



Body much elongated, mantle united to the neck by three mus- 

 cular commissures. Siphon without a true valve, but with three 

 peculiar, special thickenings, or raised processes* in its basal portion. 

 Eyes prominent. Intestine very long ; ink-sac small. 



Desmoteuthis Yemll. (See p. 300). 



1 2. Desmoteuthis hyperboreus (Steenst.) Verriii. (p. 302). 



13. Desmoteuthis tenera Yerrill. (p. 412). 



Taonius Steenstrup, restricted. (See p. 306). 



14. Taonius pavo (Les.) steenstrup. (See p. 306). 



MYOPSID^E D'Orbigny. 



Eyes usually without regular lids ; the integument of the head 

 sometimes becomes transparent and extends continuously over the 

 eye; in some genera (Hossia, &c.) there is a fold of skin below the 

 eye, constituting a free lower eyelid, Avhile the upper lid is adherent 

 to the eye-ball ; but in Stolotevthis the lids are entirely free. The 

 pupil is usually crescent-shaped, or indented on the upper side, btit 

 is round in Stoloteuthis. Sometimes a small pore in front of the 

 anterior edge of the eye connects with the orbital cavity. Siphon 

 usually with a valve. 



This artificial division includes two very diverse groups, which not 

 only differ widely in the condition of the eyes, but also in the nature 

 of the hectocotylization of the arms, and in anatomical characters. 



To one of these groups, containing the family SeplolidcB, I propose 

 to fipply the name Sepiolidea. 



The other division, Sepidea, includes the families, Sepidce, Loli- 

 ginidci', Idiosepid(X, and perhaps Spirulidce; but the latter might, 

 perhaps, be best placed with fossil forms in a division of which it is 

 the sole surviving genus. 



* Of these orpraiis the median dorsal one is larger and more complicated than the 

 others (see PI. LV, fig. 2d, m; and fig. 4a.). It seems to me probable that this organ 

 is a true hornologue of the foot of gastropods. 



