The Ship Worm 



In temperate waters T. navalis is about six inches long, when 

 full grown. In the tropics it is often two feet long. Ordinarily 

 the shell itself is never larger than a small hazel nut; the pallets 

 grow to two inches in length. There is a related mollusk, Kuphus 

 arenarius, Linn., living in sands in the Philippines, which has a 

 tube two yards long, somewhat like the watering-pot's trum- 

 pet-like spout. 



A boring isopod, Limnoria lignorum, shares with the Teredo 

 the blame for destroying wood exposed to sea water. This crea- 

 ture actually swallows its chips. It subsists upon wood. Teredo 

 feeds upon microscopic organisms taken through the incurrent 

 siphon from the water. It asks lodging, but not board, too; 

 so it asks less than Limnoria does. 



A good word for Teredo navalis. It clears harbours of wooden 

 debris; the hulks of derelicts, floating and sunken timbers, up- 

 rooted and drifting trees, all of them hidden dangers to naviga- 

 tion, until they crumble as the result of the perforation of their 

 fibres by the ship worm. It is a scavenger of sea coasts. 



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