STRUCTURE OF CORAL REEFS. , 129 



Coral-reefs are sometimes viewed as only traps to surprise 

 and wreck the unwary mariner ; but whoever has visited the 

 dreary prison-house, St. Helena, will have some appreciation of 

 the benefits derived from the growing zoophytes. 



But in addition to these general benefits, there are also 

 contributions from the larger reef regions to the commerce 

 of the world. Besides pearls, there is the biche de mat 

 (called also bkhe de nier, sca-ginse;ig, and in China, tripang), 

 thousands of hundredweight of which annually enter the 

 Chinese market from the reef-regions of the East Indies, Aus- 

 tralia, and the seas to the north, including the Feejee Archi- 

 pelago. This favourite material for Chinese dishes, either stews 

 or soups, &c., is dried holothicria — large slug-like animals, 

 called often sea slugs, and also sea cucumbers, from their form 

 in tlie contracted state. They are not slugs, but are most 

 nearly related to the echinus, though having a thick flexible 

 skin, while the echinus has for its exterior a firm shell, armed 

 about with spines. The largest are only nine or ten inches 

 long when contracted ; but they lengthen out sometimes to 

 two feet or more. They live just under the sand in the shal- 

 low waters, with the head projecting and bearing a beautiful 

 feathery rosette or flower which is branchial in nature. To 

 fit them for exportation, the holothuria, of which half a dozen 

 different kinds are taken, are slit open, boiled, and then dried, 

 in which last state they look like "smoked sausages." Dr. S. 

 Wells Williams says, in his " Middle Kingdom," that " when 

 soaked in water, the material resembles pork rind, and is Hke 

 that in taste when stewed." They are brought to China by the 

 Malays from Macassar and elsev/here. There are also large 

 drying-houses at the Feejees, and ships from America make 

 their occasional visits to collect them, with the aid of the Fee- 

 jees, and to dry and load up for China. The term biche de mar, 

 and also the French form of it, beche de 7ner, are corruptions 

 of the Portuguese bicho do mar, which means sea-wjrm, or 

 sea-sbis:. 



