SHARKS AND SKIPPERS 151 



mouth. With this splendid instrument the creature grips 

 and breaks off or gnaws off, or bores out crumbs of coral 

 which you find, apparently in process of digestion, as you 

 render him an acceptable morsel. Scientific observers 

 affirm that by means of an acid which the Echinus secretes, 

 it disintegrates the rock, and that the jaws are used merely 

 to clear away the softened rubbish. How is it then that 

 the globular cavity is often well-ballasted with tiny 

 crisp chunks of coral rock ? Possibly to the assimilation 

 of the lime is due, in some measure, the singularly sweet 

 and expressive savour. So we see the coral-reef-building 

 polyps toiling with but little rest, almost incessantly labour- 

 ing to raise architectural devices of infinite design, and 

 other creatures as industriously tearing them down to form 

 the solid foundation of continents. 



Another species of Echinus eludes its enemies by the 

 adoption of a cumbersome and forbidding mask. Ineffec- 

 tively armed, the spines though numerous being short and 

 frail, it holds empty bivalve shells on its uppermost part. 

 The unstudied accumulation of debris — a fair sample of 

 the surrounding ocean floor — would fail to fix notice, but 

 that it moves bodily and without apparent cause. Inspec- 

 tion penetrates the disguise. Wheresoever the Echinus 

 goes — its progress is infinitely slow — it carries a self- 

 imposed burden — the refuse of dead and inanimate things 

 — that it may, by imposition upon its foes, continue in the 

 way of life. 



Sharks and Skippers 



Local blacks have no fear of sharks. They take every 

 care to avoid crocodiles, exercising great caution and 

 circumspection when crossing inlets and tidal creeks. So 

 shrewd are their observations that they will describe 

 distinctive marks of particular crocodiles and indicate 

 their favourite resorts. Their indifference to sharks is 

 founded on the belief that those which inhabit shallow 

 water among the islands never attack a living man. 



