35 8 THE ARGONAUT, OR PAPER NAUTILUS. 



In these animals, which are, as has already been mentioned, thought by manj 

 naturalists to be above the molluscs, the organization is highly developed. The nervous 

 system is more like that of the vertebrates than is the case with any other kind of 

 mollusc, the knot of ganglia in the head bearing no small resemblance to a real brain. 

 The Cephalopods breathe by means of a pair of gills or branchiae, one set on each side 

 of the body, and the circulating system by which the blood is driven through those 

 organs and thence to the remainder of the structures is very complete. 



They are all animals of prey, and are furnished with a tremendous apparatus for 

 seizure and destruction. Their long arms are furnished with round, hollow disks, set 

 in rows, each disk being a powerful sucker, and, when applied to any object, retaining 

 its hold with wonderful tenacity. The mode by which the needful vacuum is made is 

 simple in the extreme. The centre of the disk is filled with a soft, fleshy protuberance, 

 which can be withdrawn at the pleasure of the owner. When, therefore, the edges of 

 the disk are applied to an object, and the piston-like centre with drawn, a partial 

 vacuum is formed, and the disk adheres like a cupping-glass or a boy's leather 

 sucker. 



These disks are all under the command of the owner, who can seize any object with 

 an instantaneous grasp, and relax its hold with equal celerity. The arms are almost as 

 movable and as useful to the cuttle-fish as the proboscis to the elephant, for beside 

 answering the purposes which have been mentioned, they are also used as legs and 

 enable the creature to crawl on the ground, the shell being then uppermost. 



We will now proceed to a few selected species of Cephalopods, and in the course of 

 describing the several individuals, will examine the curious ->oints of structure which 

 are common to all. 



OUR first example is the celebrated ARGONAUT, or PAPER NAUTILUS, the latter title 

 being given on account of the extreme thinness and fragility of the shell, which crum- 

 bles under a heedless grasp like the shell of an egg, and the former in allusion to the 

 pretty fable which was formerly narrated of its sailing powers. It is rather remarkable, 

 by the way, that the shell of the Argonaut is, during the life of its owner, elastic and 

 yielding, almost as if it were made of thin horn. 



Two of the arms of the Argonaut are greatly dilated at their extremities ; and it was 

 formerly asserted, and generally believed, that the creature was accustomed to employ 

 these arms as sails, raising them high above the shell, and allowing itself to be driven 

 over the surface by the breeze, while it directed its course by the remaining arms, which 

 were suffered to hang over the edge of the shell into the water and acted like so many 

 oars. In consequence of this belief, the creature was named the Argonaut, in allusion 

 to the old classical fable of the ship Argo and her golden freight. 



Certainly, the Argo herself could not have carried a more splendid cargo than is 

 borne by the shell of the Argonaut when its inhabitant is living and in its full enjoy- 

 ment of life and health. The animal, or " poulp " as it is technically called, is indeed a 

 most lovely creature, despite of its unattractive form. " It appeared," writes Mr. Rang, 

 when describing one of these creatures which had been captured alive, " little more 

 than a shapeless mass, but it was a mass of silver with a cloud of spots of the most 

 beautiful rose-color, and a fine dotting of the same, which heightened its beauty. A 

 long semicircular band of ultramarine-blue, which melted away insensibly, was very 

 decidedly marked at one of its extremities, that is of the keel. A large membrane 

 covered all, and this membrane was the expanded velation of the arms, which so pecul- 

 iarly characterizes the poulp of the Argonaut. 



The animal was so entirely shut up in its abode, that the head and base of the arms 

 only were a very little raised above the edges of the opening of the shell. On each 

 side of the head a small space was left free, allowing the eyes of the mollusc some scope 

 of vision around, and their sharp and fixed gaze appeared to announce that the animal 

 was watching attentively all that passed around it. The slender arms were folded 

 back from their base, and inserted very deeply round the body of the poulp, in such a 

 manner as to fill in part the empty spaces which the head must naturally leave in the 

 much larger opening of the shell." 





