AND THE MALES OF CERTAIN CEPHALOPODS. 121 



seminal thread contained in a spermatophore. Besides these 

 organs, Cuvier describes the muscular tube forming the axis of 

 the body, and continuous with a filament folded up in the ter- 

 minal sac, a filament which we have called the flabellum. 

 According to Cuvier, the point of this flabellum is bent back 

 into the body of the animal, and is directly continuous with the 

 seminal thread. We know not to what circumstance we must 

 attribute this mistake, for in all the specimens we have exa- 

 mined, the flabellum has been found completely free at its ex- 

 tremity. 



The note which was published at a later period by M. Costa 

 of Naples, upon the Hectocotylus Argonautae*, only added to 

 the controversy the opinion of the author, who looks upon this 

 animal as the spermatophore of the Octopus. M. Costa's de- 

 scription is besides altogether incorrect, and the figure is as bad 

 as it can be. The sac of the flabellum is represented like a 

 pennant ; the extremity of the true spermatophore as a tenta- 

 cular cirrhus with two points ; the convolutions of the seminal 

 thread appeared to M. Costa to be spots formed by little spiral 

 vessels. 



M. Dujardin, in arranging the Hectocotyli among the doubtful 

 Trematoda, thus gives his opinion upon these parasites f * " I 

 have seen the anatomical preparations preserved in the Museum, 

 as well as an entire specimen ; but I confess I cannot compre- 

 hend what the thing can be ; I am only clear that it is not a 

 Trematode worm. One might call it an arm torn from some 

 other Cephalopod, so similar is the double series of suckers oc- 

 cupying the ventral surface of the Hectocotylus to the larger 

 suckers of the Octopus : the internal structure is equally mus- 

 cular, but there is visible in the dorsal portion a long white 

 sinuous and folded thread, which Cuvier could detect only after 

 the action of spirit, and which therefore should proceed from 

 the coagulation of some liquid (spermatic?) substance " 



" It can only be by the study of these objects in the living 

 state that we can decide upon their true nature, and determine 

 if they be not the portions of some Cephalopod detached in order 



* Note sur le pretendu parasite de I 'Argonauta Argo (Ann. d. Sc. Nat. 

 2 f serie, t. xvi. 1841). 



t Dujardin, Histoire Naturelle des Helminthes ou Vcrs Intestinaux (Suites 

 a Buff on, 1848). 



