AND THE MALES OF CERTAIN CEPHALOPODS. 139 



through the sac. We see then, that in consequence of the very 

 arrangement of the parts, the seminal masses carried by the 

 deferent canal ought to meet in this common reservoir with the 

 product of the secretion of the accessory gland, and to enter 

 with it into the flask. It is probable therefore that here, in this 

 wide sac with delicate walls, the spermatic machines are formed 

 and pass afterwards into the flask. 



The latter organ (PI. III. fig. 1-4.) is situated, as we have al- 

 ready said, upon the ventral face of the intestinal sac immediately 

 under the fibrous envelope which surrounds the latter. The mem- 

 brane wliich forms the flask is very delicate, very contractile, and 

 almost impermeable to water. In its interior we see undulating 

 brilliant white lines, such as we have described above, and which 

 are sometimes so obvious that they might be taken for external 

 ornaments of the envelope. The semilunar aperture situated 

 close to the neck of the flask is generally very difficult to per- 

 ceive, and opens only after a prolonged stay in the water to give 

 exit to the contents of the flask, which are formed in all the in- 

 dividuals we have examined by a unique spermatic machine, — 

 by a single spermatophore filling the whole cavity so completely, 

 that it is very difficult to open the latter without damaging the 

 spermatophore contained in its interior. 



This enormous spermatophore (PL iV. fig. 1.), which is nearly 

 two centimetres in length, is always folded up in the flask, so that 

 both its extremities approach the semilunar aperture of the latter. 

 Removed from the flask the spermatophore has the shape of a 

 powder-horn, having one extremity pointed and elongated into 

 a beak, the other enlarged and rounded. The beak, although 

 the more firm and consistent portion, is however almost trans- 

 parent, whilst the sac appears almost white, by reason of the 

 convoluted silvery thread which it contains in its interior. The 

 spermatophore itself is formed by a very solid membrane, per- 

 fectly transparent, which, after having formed the sac, is con- 

 tinued upon the beak-like prolongation, surrounding it very 

 closely. This envelope absorbs water very quickly, and svTells 

 out rapidly in consequence ; it becomes separated then into two 

 layers, the exterior of which, very delicate, forms irregular folds, 

 often so multiplied that one might imagine the beak of the sper- 



Imatophore to be constituted here and there by the convolutions 

 I 



