822 . CLASS xni. 



been developed in its own proper vesicle within the larger bladder, and 

 of which the remains continue attached at the extremity of the hec- 

 tocotylus after it has allowed the filament to escape). The filament is 

 tubular, its cavity is continuous with that of the hectocotylus, and is 

 open at its extremity. The tube of the elongated pouch runs in the 

 central cavity of the hectocotylus and of its continuation, the fila- 

 ment, and opens at the extremity of the latter externally. The 

 pouch or sac is found, when the hectocotylus is fully developed, to 

 contain a spermatophore, and it was the presence of spermatozoa 

 and of an organ apparently for the secretion of them in the interior 

 of the hectocotylus, when found attached to the respiratory cavity of 

 the Argonauta, that induced KOELLIKER to suppose the Hectocotylus 

 to be the male of the Argonauta. H. MUELLER found this Hectoco- 

 tylus in its state of imperfect development on that male, which is 

 much smaller than the female, and has no shell 1 . The hectocotylus 

 arm is the second of the left side in A. Argo, the third of the right 

 side in Octopus granulosus, (Tremoctopus Carena VER.) whilst the 

 hectocotylus only, and not the male of Tremoctopus violaceus DELLE 

 CHIAJE, has hitherto been discovered. 



The sexual organs of the hectocotyliferous males are constructed 

 on exactly the same plan as those of the males of ordinary Cephalo- 

 pods. The vas deferens opens at last into the respiratory sac, so 

 that the idea of a communication between it and the sac of the hec- 

 tocotylus arm, entertained by some, is untenable. How then is the 

 spermatophore transferred to this sac 1 ? VoGT 2 thinks that the spot- 

 ted pocket (the bladder in which the hectocotylns was originally de- 

 veloped, and which is now turned inside out, with a fissure 

 through which the arm has passed) serves as a receptacle for the 

 spermatophore, which has been transferred to it by the long filament 

 of the hectocotylus embracing it ; at the same time he denies the ex- 

 istence of the muscular sac in the interior. LEUCKART 3 , however, 

 has established the existence of this last, and has found a communi- 

 cation between the spotted bladder and the side of the muscular sac 

 attached to it, namely a canal by which they communicate. It is not 



1 See H. MUELLER Ueber das Mannchen von Argonauta Argo und die Hectocotylen, 

 SIEBOLD u. KOLLIKER'S Zeitschr. fur wissensch. Zool. iv. 1852, pp. i 35, PI. I. ibid. 

 pp. 346359- 



3 VERANY et VOGT Sur la not. des Hectocotyles, Ann. des Sc. nat. T. xvn. pp. 148, 

 191, PL 69, at p. 155. 



3 LEUCKART Die Hectocotylie von Octopus Carena, Zool. Untersuch. Heft in. Gies- 

 sen, 1854, pp. 91109, Tab. 2, at p. 103. 



