ARGONAUTA ARGO AND THE HECTOCOTYLI. 67 



with Kolliker (pp. 79 & 80) that this aperture belongs to the 

 seminal capsule. Whether a second aperture for this exists at 

 the anterior end is not certainly determined by Cuvier himself, 

 and he does not state that Laurillard had seen the semen poured 

 out anteriorly. The connexion which, according to Cuvier, exists 

 between the thread (i) everted from the terminal vesicle, on the 

 one hand with the axis of the body, and on the other with the 

 canal (h), which, coming from the seminal capsule, is evidently 

 analogous to the ductus deferens in the Argonaut, is singular. 



If with KoUiker we may be permitted here to suppose an 

 error on the part of Cuvier, who only examined spirit speci- 

 mens, I should imagine, keeping in view the fact that Verany 

 found a filament with a free and pointed end in the terminal 

 vesicle of the Octopus, that the latter was overlooked by Cuvier. 

 If this be the case, the analogy between the filament exserted 

 from its vesicle and the filamentous appendage (penis) of Hecto- 

 cotylus Argonautce becomes striking. 



It would then require to be made out whether and how this 

 appendage makes its exit from its vesicle, and we might con- 

 ceive similar relations to those which I shall subsequently show 

 obtain in Hectocotylus Tremoctopodis, In the latter case the 

 presumed error of Cuvier would be easily explicable. The above- 

 mentioned differences in the position of the pigmented sac 

 might also be connected with the difference in the position of 

 the appendage, since in Hectocotylus Octopodis the supposed 

 appendage is perhaps never meant to pass into that pigmented 

 capsule as in Hectocotylus Argonautce, 



From the structure of the Hectocotylus Octopodis, especially 

 the presence of the silky thread in the capsule, e, and the asser- 

 tion of Dujardin {Helminthes, p. 131) that the white thread 

 consists of spermatozoa, the male nature of this Hectocotylus also 

 may be concluded. 



Its development is probably quite similar to that of the Hec- 

 tocotylus of the Argonaut. 



Verany and Filippi (see above) have already proved that the 

 Hectocotylus of the Octopod arises as one of its arms. Verany 

 has observed in the same place a sac, which, according to the 

 figure in which chromatophora are indicated, appears rather to 

 be analogous to the sac of the male Argonaut than to the 



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