38 OCEAN LIFE. 



prey in ambush ; but what that prey is, as well as the entire 

 economy of these Moluscs, remains a perplexing mystery. Their 

 intestines invariably contain many hard and solid masses of 

 madreporic rock or tree-coral, some of them more than an inch 

 in length, and all moulded as pellets to the calibre of the intes- 

 tinal canal. It is difficult to say how these stony bodies have 

 been obtained by the Trepang, though it is easy to conceive that 

 they may be rendered serviceable as nutriment by the assimila- 

 tion of the animal matter they contain. It is this animal which 

 the Malays of the Oriental Isles seek so diligently, for the supply 

 of the China market, where it obtains a good price when well 

 preserved. It is employed by the Chinese in the preparation of 

 nutritious soups, in common with an esculent sea-weed, Shark's 

 fins, edible bird's nests, and other materials, affording much 

 jelly.' Jaeger says the intestines are extracted, the animal then 

 boiled in sea-water, and dried in smoke." 



CRUSTACEA. 



" THE Crustacea pre-eminently make the waters their home ; 

 they are the aquatic division of that mighty host of living things, 

 that range under the title of ARTICULATA. In most respects, 

 CRUSTACEA are so much like insects, that the older naturalists, 

 and the illustrious Linngeus among the number, arranged them 

 under the great class INSECTA. They have, however, a greater 

 number of limbs ; the full provision being five pairs of true feet, 

 and three pairs of organs, which 'are called foot-jaws. Besides 

 these, a great number of the species have five or six pairs of 

 jointed limbs attached to the underside of the abdomen, which 

 are generally used for progression, and are called false feet. 

 Their mouth is furnished with three pairs of jaws and two pairs 

 of antennae. It must be borne in mind, however, that the total 

 complement of these members is not found present in every spe- 

 cies, some of them being wanting in certain extensive groups. 

 The researches of a naturalist who has paid much attention to 

 this class, Mr. Spence Bate, have shed a flood of interesting 

 light on the office of the organs last-named. Any one may easily 



