322 NATURAL SCIENCE. Nov., 



occasions a savage combat between the two. Mr. Racovitza, 

 however, assures us that there is nothing more than a courteous 

 flirtation, and that " the male behaves with a certain deHcacy towards 

 his companion." Placed at a considerable distance from the female, 

 the male stretches out the third arm on the right, which is known as 

 the hectocotylised arm, and with its extremity he caresses her, 

 eventually passing it into the chamber formed by the mantle. The 

 female contracts spasmodically, probably because the arm touches 

 the gill, but does not attempt to move. The animals remain in this 

 passive condition for an hour or more, but at about half-time the 

 male shifts the end of the hectocotylised arm from the opening of one 

 oviduct to that of the other : this gives rise to fresh contractions on 

 the part of the female, and at the same time the m^ale has been seen 

 to eject a thick cloud of ink. Should the female prove at all refrac- 

 tory, the male stiffens one of the arms of the second pair, and raises 

 it with a warning motion, as a schoolmaster might raise his cane. 

 With the same gesture the Octopus, turning black with anger, 

 threatens any intruders, and in both cases the menace is successful. 

 Finally the male withdraws his arm from the mantle-chamber, 

 caresses the female with it for a few moments, and then places it in 

 the same position as his other arms. 



As regards the actual mechanism by which the spermatozoa are 

 transferred from the body of the male to the ova, Mr. Racovitza has 

 also something new to add. It is well known that the spermatozoa 

 of Cephalopoda are ejected in special tubes or cases called spermato- 

 phores ; and it is generally stated that the male introduces the end of 

 his arm into the mantle-chamber to take a packet of spermatophores, 

 which he then places in the mantle-cavity of the female. This 

 statement, however, is not based on direct observation : " It has 

 sprung," says Mr. Racovitza, " from the simple imagination of a 

 single author, and has been repeated by everybody without having 

 been brought to the test of either facts or logic, just as is so often the 

 case, especially in the natural sciences." The true facts, so far as 

 Octopus vulgaris is concerned, appear to be as follow. The spermatozoa 

 are contained in the round head of a tubular spermatophore. The 

 spermatophore is expelled from the opening of the penis, which 

 stretches out, through the mantle-chamber, into the funnel, which 

 then conducts it to the base of the hectocotylised arm. Down this 

 arm there runs a channel or gutter, lined by smooth epithelium, which 

 is thrown into numerous minute folds. Wave-like contractions 

 traversing the walls of the gutter force the spermatophore along this 

 channel to the distal end of the arm, which, as already stated, is 

 placed in the mantle-chamber of the female. The flattened end of 

 the arm then apphes the head of the spermatophore to the opening of 

 the oviduct, in which position it comes in contact with the sea- 

 water and bursts, so that the spermatozoa are set free into the canal 

 of the oviduct. The walls of this canal are provided with numerous 



