in the Cephalopoda. 101 



of Chili, and which is principally distinguished from the other 

 species of Octopus by the character which I have found to occur, 

 and indeed in a remarkable degree, in all male individuals of our 

 commonest species, is probably established only upon males, and 

 is perhaps also a collective species, consisting of males of several 

 distinct species. At all events, two male Octopods from the 

 coast of Chili which I possess, present, together with the com- 

 mon character of these large suckers on a particular part of the 

 arm, such great differences, that they can hardly be regarded as 

 belonging to a natural species : one of them, a very large speci- 

 men, of the size of an ordinary O. vulgaris, has 90 pairs of 

 suckers on the third right arm ; the other, which was brought 

 from Valparaiso by Professor Kroyer, is much smaller, and has 

 only 40 pairs of suckers on the same arm ; the large one has 

 the terminal plate but slightly developed, whilst the hectocoty- 

 lized arm of the smaller specimen bears an elongated, lanceolate, 

 terminal plate with faint transverse wrinkles, and the angle of 

 the fold of skin previously mentioned is drawn out into a papil- 

 liform point (fig. 4) ; the small male also has the isolated, dis- 

 proportionately large suckers on the dorsal and ventral as well 

 as on the lateral arms, and the latter are not thicker than the 

 uppermost and lowest pairs, whilst the large male has these large 

 suckers only on the lateral arms, which preponderate consider- 

 ably over the other arms. Now, as I am also in possession of a 

 female Cephalopod which approaches the smaller male, but is 

 destitute of those suckers, I believe I am justified in expressing 

 my above-mentioned suspicion against 0. Fontanianus ; but I 

 must reserve myself for a final decision by more abundant ma- 

 terial. At present I must advise naturalists to be cautious about 

 admitting the whole group of Octopods which Gray wishes to 

 bring together by a character which at least partially coincides 

 with the most essential specific character hitherto given for O. 

 Fontanianus ; according to Gray, the males of Octopus vulgaris 

 would come in this, his third group, whilst the females would 

 remain in his first*. 



A male individual of the genus Eledone, Leach, which is de- 

 rived from the Mediterranean, and which, as it has a cirrus over 

 the eye, would most probably be the common E.moschata, Leach, 

 shows that this nearly allied genus possesses a similar structure 

 of the arms, as is shown more exactly in PI. IIL fig. 5. As in 

 the genus Octopus^ the third right arm is shorter and somewhat 

 stronger than the left one ; it bears only 64 acetabula, whilst 



* Gray, Catalogue of the MoUusca in the Collection of the British Mu- 

 seum, Part 1. London, 1849, p. 14. With regard to the O. oculatus. 

 D'Orb., which also stands in Gray's third group, I can at least certify that 

 only the males possess the veiy large sucker on the lateral arras. 



