How Animals Work. 



delicate tube, as thin as paper, composed entirely of 

 grains of sand which have been most carefully selected, 

 and cemented together by a natural and copious secre- 

 tion. The walls of the slightly conical and curved tube 

 do not exceed a single grain of sand in thickness, they 

 are beautifully smooth without, and are lined within 

 with a thin silky film of secretion. Building opera- 

 tions are generally carried on at night, for Golden-head 

 is a shy little fellow; but when engaged in lengthen- 

 ing or repairing his tube, he spreads his tentacles 

 abroad, gathering and selecting sand grains of a given 

 size, rejecting all others that may come to hand, moisten- 

 ing each grain with, cement ere placing it in position. 

 The finished tube is open at both ends, and the little 

 worm carries it along when moving over the floor of 

 the sea. 



But now I would ask you to quit the seashore for 

 a while, leaving its wealth of marvellous forms of animal 

 life, that we may journey inland and visit some quiet, 

 reed-bordered fish pond, whose surface, diapered with 

 the leaves of many a water plant, reflects the image of 

 the overhanging willows and the soft white clouds 

 that sail like silver argosies across the summer sky. 

 Beneath the surface of that quiet pool, could we de- 

 scend (and at the same time diminish in size until 

 we dwindled to the microscopic proportions of its 

 smaller inhabitants but still retained our powers of 

 vision and understanding), what a strange world we 

 should enter a world peopled by " creatures that swim 

 with their hair, that have ruby eyes blazing deep in 

 their necks, with telescopic limbs that now are with- 

 drawn wholly within their bodies and now stretched 



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