Corals, Worms, etc. 



that they are drawn into a hole by the part where the 

 two leaves join and that the pointed, needle-like tips of 

 the leaves are pushed into the earth at the side of the 

 burrow, so that they may not damage the inmates' 

 delicate skins. 



Perhaps in our gardens we may have dug up the cocoon 

 of the earthworm without knowing it. They are white when 

 first formed, turning yellow later, rounded at one end 

 and almost pointed at the other. Their mode of forma- 

 tion is peculiar. On examining an earthworm we cannot 

 fail to notice, about one-third of the way down its body, 

 a light-coloured ring. When about to lay eggs, the worm 

 gives off a sticky substance which, in contact with the air, 

 rapidly becomes hard and horny. As this ring is formed, 

 the worm withdraws and at the same time deposits three 

 or four eggs within it. When free of the worm, the ends 

 of the ring close up to form the cocoon. Later a single 

 worm emerges, a perfect worm in miniature, which 

 completes its development in the cocoon at the expense 

 of the other eggs. 



That earthworms do a great deal of good is undoubted. 

 Darwin estimated that the average garden in this country 

 contains 53,000 earthworms and that ten tons of soil per 

 acre pass through their bodies each year, or, in other 

 words, that the earthworms of England pass 320,000,000 

 tons of earth per annum through their bodies. " In the 

 history of the habitable earth, earthworms have been the 

 most important feature in progress. Ploughers before 

 the plough, they have made the earth fruitful." 



The earthworms belong to the class of bristle-footed 

 worms because they move from place to place by means 

 of minute bristles which project from their bodies. In the 

 sea there are many interesting worms of the same class. 

 The little sand-mason is one of them. So delicate is this 

 creature that it builds for itself a tube of sand in which it 

 dwells. In appearance it is quite unlike the earthworm ; 

 round its mouth there is a fringe of tentacles, and with 



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