Corals, Worms, etc. 



the name of "trepang," is considered a delicacy in China. 

 Many of these animals carry their young on their backs 

 till they are able to fend for themselves.. 



The worms, in the broad sense of the word, are an 

 exceedingly interesting group of the animal kingdom. 

 As an engineer the common earthworm has few rivals, or 

 should we more fitly call him a tiller of the soil ? Each 

 earthworm forms for himself a burrow which varies in 

 depth from about eighteen inches in summer weather to 

 as much as six or seven feet in dry, cold weather. These 

 excavations are made in the simplest possible manner, for 

 the worm simply pushes its way through the earth and 

 swallows the soil as it goes. The digestible matter, in the 

 form of decayed vegetable matter, goes to build up the 

 tissues of the little burrower, the indigestible substances 

 pass through the earthworm's body to form the familiar 

 worm castings. Occasionally, however, the worm plasters 

 this finely divided soil which has passed through its body 

 against the sides of its burrow, by means of its flattened 

 tail. In this manner it provides a smooth lining for its 

 home and one, moreover, which it covers with a slimy 

 substance from pores in its back, a substance which forms 

 both lubricant and antiseptic against the advent of 

 harmful bacteria. 



By day the worm lives below ground, at night it sallies 

 forth in search of food, but always keeps the tip of its tail 

 just within the entrance to its burrow, the reason being 

 that on the least hint of danger it is thus enabled to fly back 

 into safety. Cold and damp are distasteful to earthworms, 

 and, in addition, they have many enemies ; it is not sur- 

 prising, therefore, to learn that they plug the mouths of 

 their burrows with leaves. As Darwin pointed out, they 

 do not do this at random. Each leaf is carefully 

 examined till the narrowest part is discovered, and this 

 is the part which is drawn first into the burrow. 



At times these leaves are used to line the burrow, and 

 when Scotch pine is used for the purpose Darwin noticed 



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