200 ' J. GRAHAM KERR. 



The remarkable organ formed has been referred to by 

 Valenciennes', and by Lankester^, as a paired structure. Not 

 always, however, does it seem to be so, as in one of the two 

 specimens in which I observed it the laminae were quite con- 

 tinuous across the middle line, the laminae appearing in fact to 

 be mere exaggerations of the fine transverse wrinkles into 

 which the surface of the skin is thrown behind the lamellar 

 organ. Of the two authors referred to, the first, after some 

 hesitation, suggests that the lamellated organ may be tactile 

 in function, "analogous to the palpi round the Crustacean 

 mouth." Lankester, on the other hand, for what reasons is not 

 stated, very definitely describes the organ as "probably 

 olfactory'." 



During the examination of a mature female somewhat 

 startling evidence was obtained as to the true function of this 

 organ. The lamellae were here covered with a thick coagulated 

 material apparently secreted by them, spreading over the edges 

 of the lamellae and passing in thin plates down between them. 

 Partially imbedded in the coagulum on the left side and only 

 partially visible, there appeared a peculiar brown structure 

 which at once suggested the appearance of a sperm atophore. 

 And upon carefully clearing away the surrounding material the 

 surmise so suggested was corroborated. The long slender 

 spermatophore lay coiled backwards and forwards over the 

 surface of the lamellae in the manner indicated in PI. X. fig. 2, 

 held firmly in position by the coagulated material. 



We would seem to have here a peculiar cement-secreting 

 glandular apparatus, on whose sticky surface the spermatophore 

 is deposited by the male. 



In other Cephalopoda the position in which the spermato- 

 phore is attached to the female varies : in (Egopsids, Octopods, 

 and Sepiola, e.g., it is passed into the mantle-cavity ; in other 

 Decapods (e.g., Sepia, Loligo) it is attached to the skin on the 

 outer surface of the buccal mass. In Nautilus the position is 

 thus a somewhat intermediate one. 



' Arch. Mus. d'Hist. Nat. torn. ii. p. 277. ^ Zoological Articles, p. 130. 



3 Op. cit. fig. 88. 



