THE IMPENETRABLE SEA 



parts — along the ''keel". The lady is entirely enclosed in 

 her abode, and it has been doubtfully reported that she 

 leaves the craft to forage about in its neighbourhood, 

 propelling herself by her siphon like any ordinary 

 cephalopod. 



Within the shell she lays her eggs, already fertilized 

 by the male, and these are suspended in a grape-like 

 cluster attached to the interior of the spire. If she is 

 swimming around outside the shell and is attacked she 

 gets back into her shell like lightning to protect her eggs, 

 curling herself inside her strange craft until almost hidden. 



The real purpose of the expanded arms is to cover the 

 exterior of the shell, and to build up its delicate structure 

 and repair any damage to it : the substance of the delicate 

 shell being secreted by these arms. The lady uses them to 

 mould the substance into shape, so that (despite their 

 clumsy appearance and apparent simplicity of structure) 

 her arms are used like the hands of a sculptor. 



To obtain a mental picture of the nautilus looking out 

 of her home, think of some large sea-shell that you have 

 seen — one with graceful ridges — and give it graceful lines 

 and artistic embellishments. Realize that this shell is 

 made of extremely thin material, and then imagine a 

 curious 'Tace", in profile, protruding from it — its main 

 characteristic being a perfectly round staring eye. Instead 

 of a nose or chin, imagine a number of slender, tapering 

 appendages projecting from the 'Tace", held closely to- 

 gether and rippling slightly as the creature stares at you. 

 There you have the paper nautilus guarding her eggs — 

 one of the sea's most beautiful creatures, on acquain- 

 tance, although not at first sight. 



The paper nautilus, or argonaut, must not be confused 

 with the pearly nautilus — an entirely diflferent creature. 

 Many legends describe the pearly nautilus ''sailing the 

 seas", and how she will "spread the thin oar and catch 

 the rising gale". The fact is that (unlike the Portuguese 

 man-of-war) she is really a bottom-of-the-sea species that 



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