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I N A G U A 



remain, all occurring in the South Pacific. 



To compensate for the loss of their shells, which were their 

 bulwarks against fate, these unclothed cephalopods have de- 

 veloped, like man, cunning and intelligence. Alone among the 

 molluscs they have acquired by concentration of their chief 

 nerv^e ganglia w^hat may be truly considered a brain. With the 

 casting aside of the shell they have also gained their freedom, 

 speed and mobility. 



Safety often goes hand in hand with degeneration. It is a 

 curious circumstance that those creatures which live com- 

 pletely guarded lives also have a very dull existence. What, 

 for example, could be safer and more stupid and sedentary than 

 an oyster, clad in its house of lime? The loss of a shell not only 

 rescued the cephalopods from dullness but it probably also 

 saved them from extinction. The most highly ornate shelled 

 cephalopods of all time, the gracefully coiled Ammonoids, 

 which are so named because of their resemblance to the ram- 

 like horns of the deity Jupiter Ammon, and which developed 

 during the Upper Silurian and lasted until the close of the Age 

 of Reptiles, went out of existence because the extent of their 

 external sculpture and complexity of septation rendered them 

 so specialized that they failed to respond to change. Some of 

 these fantastic Ammonoids, of which six thousand species are 

 known, possessed coiled shells more than six feet in diameter! 



"Cephalopods," the scientific name of the octopi and squids, 

 immediately characterizes them as something unusual, for it 

 signifies that they walk on their heads. This is precisely what 

 they do, for their tentacles or "feet" are located between their 

 eyes and mouths. No other animals on earth utilize this position 

 or method of progression. 



However, it is in their mode of swimming that the motion of 

 these weird beings is most amazing. They are beautifully 

 streamlined when in action, and can dart about at remarkable 



