678 ME. J. GRAHAM KEEE ON THE [June 18, 



ciennes\ and b,v 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 continuous 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 tbrowTi behind the lamellar organ. Of the two authors referred 

 to, the first, after some hesitation, suggests that the lamellated 

 organ may be tactile m 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 materi 

 apparently secreted by them, spreading over the edges of the 

 lamellse 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 spermatophore. A.nd upon care- 

 fully clearing away the surrounding material the surmise so 

 suggested was corroborated. The long slender spermatophore lay 

 coiled back^^"ards and forwards over the surface of the lamellae in 

 the manner indicated in PI. XXXIX. fig. 2, held firmly in position 

 <by the coagulated material. 



We would seem to have here a peculiar cement-secreting 

 glandidar apparatus, on whose sticky surface the spermatophore is 

 deposited by the male. 



In other Cepbalopods the position in which the spermatophore 

 is attached to the female varies : in CEgopsids, 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. 



VIII. The Morphology of the " Arms " of Cephalopods. 



As Grobben has justly remarked, and as Pelseneer has adopted as 

 text to his paper on the subject, " eine der schwierigsten Fragen in 

 der morphologischen Deutung des Cephalopodenkorpers bildet die 

 Morphologie der Kopfarmen "; and in accordance with this, as well 

 as with its far-reaching interest, the question has attracted from 

 time to time a great amount of attention from morphologists. 

 Hegarding the fundamental nature of these organs, two very 

 difi^erent views have been brought forward : — 



(1) That the arms of Cepbalopods are processes of the head 

 or circumoral region. 



(2) That they are processes of the foot, part of which has 

 grown up on either side so as to finally surround and 

 almost completely hide from view the head itself. 



* Arch. Mu8. d'Hist. Nat. torn. ii. p. 277. 



2 Zoological Articles, p. l.SO. = Op. cit. fig. 88, 



