genus Ocythoe of Rafinesque. 295 
racters, however, which I could not discover in th q polypus, may 
be mentioned, namely, four oblong spots on the inside of the 
tube, resembling surfaces for the secretion of mucus ; two 
inferior and lateral, and two superior, larger, and meeting 
anteriorly. On the rim of the sac, immediately above the 
branchias, on each side, is a small, short, fleshy tubercle, which 
fits into an excavation on the opposite side of the sac. This 
character, which, with slight modifications is common to this 
genus, to loligo and sepia , does not exist in the polypus * 
Although the superior arms are stated to perform such 
different functions from those of the polypus, yet they are sup- 
plied in the same manner, and from the same source with 
nerves. The muscles of these parts were in too contracted a 
state, to enable me to ascertain if they were in any degree 
different from those in the same parts of its kindred genus. 
The general form of the body of this species of ocythoe, 
is the same as that of the common polypus, and it is covered 
by the same integuments, without any surface adapted either 
to adhere to, or to secrete, the shell in which it is found. 
The sexes differ as in th e polypus » 
Ocythoe Cranchil 
O. corpore purpureo-punctato, brachiis subtus Ccerulescente- 
griseis ; superioribus membrane spongeosa pallida maculata. 
The superior arms are generally attached to the side of 
the membranes (fig. 5. PI. XII.); but in one specimen the 
membranes adhere only by their base, below the apex of the 
* The rudiment of the bone, which occurs in the polypus , (as has been observed 
by Cuvier) is not to be found in the ocythoe. 
MDCccxvir. Q q 
