496 



THE OCEAN WORLD. 



their heads. Nor did it require the dithyrambic praises with which 

 the ancients have surrounded it to recommend it to the admiration of 

 modern naturalists. Without exaggerating the graceful attributes 

 with which it is gifted, it is at once one of the most curious objects 

 in Nature. 



Its body (Fig. 336) is ovoid in form, and it is furnished with eight 

 tentacles, covered with a double row of suckers. Of these tentacles, 

 six are narrow and slender, tapering to a fine point towards the ex- 

 tremity, while the remaining two spread out in the form of wings or. 



sails. These are all folded up 

 when in a state of repose. The 

 body itself is contained in a thin, 

 white, and fragile univalve shell, 

 which is oval, flattened on the 

 exterior, but rolled up in a spiral 

 in the interior, the last turn of the 

 shell being so large as to give 

 it something of the fonn of an 

 elegantly-shaped shallop. Sin- 

 gularly enough, the body of the 

 animal does not penetrate to the 

 bottom of the shell, nor is it at- 

 tached to it by any muscular 

 ligament; nor is the shell moulded 

 exactly upon it, as is the case with 

 most other mollusca. 



What does all this imply } Is 

 the Argonaut a parasite, a fraudu- 

 lent disinheritor, a vile assassin, 

 who, having surprised and killed 

 the legitimate proprietor of the shell, has installed itself in its place, 

 and in the proper house of its victim ? Such crimes are not without 

 example in the natural history of animals — witness the proceedings 

 of the curious hennit crab, whose proceedings we shall glance at in a 

 future chapter. The parasitic character of the Nautilus was long 

 believed in by naturalists ; but recent facts have con-ected this opinion. 

 We have collected their shells, of all dimensions and of all ages, 

 inhabited always by the same animal, whose size is always propor- 

 tioned to the volume of the shell. More than that, it is now known 

 that in the egg of the Argonaut the rudiments of the shell exist. 

 M. Chenu tells us, that under the microscope Professor Duvernoy 

 discovered a distinct shell contained in the embryo. Sir Everard 



Fig. 336. — The Argonauta argo (Linnaius). 



