120 VERAXY AND VOGT OX THE IIECTOCOTYLI 



Rudolphi, although it was provided with a double series of 

 suckers, wishing, as he says, not to burden science with a new 

 genus. M. Delle Chiaje only describes the exterior of the ani- 

 mal. According to him it has a long, round, filiform, very con- 

 tractile proboscis, attenuated towards its extremity. The body 

 is provided with a double series of alternating and retractile 

 pedunculated suckers, by which the animal adheres to the skin 

 or to the shell of the Argonaut. 



M. Laurillard discovered at Nice, upon the Octopus granulosus 

 of Lamarck, five specimens of a parasitic animal, which Cuvier 

 described subsequently as the Hectocotylus Octopodis*. Among 

 these five individuals three were found in the funnel of a female 

 Octopus, one was discovered in the same position in another 

 Octopus, and the fifth individual " had attached itself to an arm 

 of the Octopus, and had transformed it into a kind of sac, into 

 which it had introduced its head, the remainder of its body being 

 external and free." In recurring to this individual, Cuvier adds, 

 " The Hectocotylus has attached itself to one of the arms, which 

 it has even almost destroyed, and which it seems to replace in 

 such a manner, that at first sight it might be taken for the 

 arm itself." With our present knowledge, we must conclude 

 from these remarks that one of the Octopods taken by M. Lau- 

 rillard was a male, which had just disengaged its hectocotyli- 

 form arm from the sac in which it had been developed. 



Cuvier describes the external form of the body, the suckers, 

 and the internal organization. None of his Hectocotyli had the 

 filiform organ, which we shall call the flabellum (lefouet), everted 

 from the sac which contains it. Cuvier found at the rounded 

 extremity of the body an alimentary orifice leading into a sac, 

 closed on all sides, and having a yellowish internal surface. This 

 cavity, which Cuvier calls a stomach, is nothing more than the 

 sac opening by a cleft, whose formation we shall subsequently 

 describe. Besides this stomachal sac, the clavate extremity 

 contains another " with stronger parietes, occupied by the innu- 

 merable folds of a thread which has the colour and brilliancy of 

 raw silk. One of the Hectocotyli ejected this thread very rapidly 

 at the moment of its capture." Cuvier is disposed to look upon 

 this thread as connected with generation. It is in fact the 

 * Annales des Sciences Naturelles, tome xviii. 1829. 



