THE HOLOTHURIADS. 



afljustcd that the perfect sj'iiimetry of the esterioi- out- 

 line remains unbrokeu. And though all are of extreme 

 ter)uity, yet they retain their pro))er positions with 

 undeviating exactness, and the sligiit brittle tenement 

 possesses all requisite strength and solidity, for each 

 |iiece is enveloped in a coat of living flesh ; a vascular 

 tissue passes up between the joints, where one meets 

 another, and spreads over the entire outer surface. 

 The glands of this tissue secrete lima froiu the sea- 

 water, and deposit it in a regular and even fashion on 

 every part of the box, so that every part is simulta- 

 neously enlarged, while the general form of tha-aninial 

 is preserved with a mathematical precision. 



The external organs of the sea-urchin are its spines 

 and tentacula — the former its instruments of defence ; 

 the latter its ambulatory appendages. Each of these 

 prickles, which vary in shape and dimensions, and 

 often exceed twelve hundred in number, is put in 

 motion by several muscles, so that the entire mechanism 

 of the animal U wondrously complex, and a marvel — 

 may we say it without profaneness ? — of ingenuity. 



The mode in which it walks is singular. The reader 

 must understand that the tentacula, or suckers, are 

 hollow internally. When filled with liquid Ihey 

 become inflated in such a manner that, at the will of 

 their owner, they can adhere to any solid body by 

 means of their terminal suckers. How is this done ? 

 Let us imagine an urchin at rest, with his spines 

 immovable and his filaments shut up wilhin their 

 shell. Some of these involuntarily escape, extend 

 them.^elves, and feel the ground all about them ; others 

 follow, yet the urcliin still remains in a condition of 

 profound tranquillity. But perhaps he wishes for a 

 change of scene, in which case he contracts his ante- 

 rior filaments at the same time that the posterior ones 

 abandon their hold, and the shell is carried forward. 

 Thus he advices, not only with ease, but even with 

 rapidity, y 



During his forward course his tentacles receive but 

 slight assistance from the spines. He can travel either 

 on his back or stomach — a convenience which is denied 

 to man 1 Whatever his posture, he has always a 

 certain number of prickles to support him, and suckers 

 with which to lake possession of a resting-place ; and 

 under certain conditions he actually walks by revolving 

 upon himself, like a wheel in motion. 



His mouth is an extraordinary organ, owing to its 

 immense size compared to that of the body. It is 

 placed underjieath the body in the centre of a soft 

 space covered with a thick defensive membrane ; here 

 it opens and shuts continually, displaying five strong 

 sharp teeth, which project from the surface and meet 

 in a point, supported and protected by a complex 

 framework, fancifully named Aristotle's Lantern. 

 These formidable grinders are set in motion by five 

 powerful muscles. 



It is needful they should be thus powerful, for they 

 are used by the animal, not only to seize and masticate 

 its food, but to excavate an asylum and a place of 

 shelter in the solid rock. Kach pick or saw, for it 

 answers both purposes, is about the eighth of an inch 

 in length. Iji oiKjning the jaws the five teeth strike 

 the stone forcibly, rather than scrape it, and thus by 



dint of continuous labour their owner obtains lor him- 

 self a comfortable lodging in the solid rock. 



S'jiinpta Duvcrnea. 



The habits of the Ilolothuria aie not known with 

 any degree of certainty or fullness. They are found, 

 however, in almost every latitude, but on sheltered 

 rocks, and secluded from the light, for which they are 

 said to cherish a special aversion. 



When held in the hand, they contract and stiffen 

 their bodies, ejecting at the same time the water with 

 which they are filled. In our European seas the 

 fisherman treats them with contempt, and they never 

 figure on the tables of the epicure or of the most 

 omnivorous fish-eater ; but among the Chinese their 

 esculent qualities are more highly esteemed, and their 

 fishery plays no unimportant part in the commercial 

 economy of the East. Oiie species, however, is held 

 in favour by the Neapolitans, the Ilolothuria iubulosa, 

 which is a native of the Mediterranean. In the Lad- 

 rone islands Holothuria guaiiiensis holds tlie place of 

 honour ; wdiile in the Malayan and Chinese seas the 

 fisher pursues the Holotliuria eduti.i^ better known by 

 the common appellation of Trepang. 



Hundreds of junks are annually employed in the 

 Trepang fishery, which is, in truth, a very amusing 

 and exciting scene for the spectator. Ihe following 

 account is condensed from the narrative of the great 

 French navigator, Dumont d'Urville, who witnes-sed 

 what lie describes in the neighbourhood of Observatoiy 

 Island : — 



Four Malay proas, flying Dutch colrurs, having 

 entered RalBes' Bay, their crews immediately set to 

 work, and in the first place commenced the erection "of 

 some curing-houses for the proper preparation of their 

 expected booty. 



Dumont d'Urville, in the course of his voyage, had 

 frequently observed little walls built up of dry slonen, 

 after the plan of a series of semicircles joined to one 

 another. He had often wondered what might be their 

 object or utility; he was now enlightened. The 

 Malays quickly deposited upon their tops several large 

 semi-cylindrical boilers, about forty inches in diameter, 

 and under these kindled enormous fires. Near to 

 tliem were constructed suitable sheds, consisting of 

 four strong posts driven into the earth, and roofed over 

 with hurdles, grass, and leaves. 



The boats, meanwhile, put out into the bay, and 

 from each some seven or eight Malays sprung over- 

 board, and commenced diving for Ilolothuria. Each 

 diver quickly returned to the surface with at least one 

 fish, and sometimes with two, as a reward of his exer- 

 tions. The 'higher the sun is above the horizon, the 

 more easily, it seems, can the creature be distinguished 

 at tlie bottom, and, mid-day is, therefore, the time 

 generally selected for fishing operations. So swift and 

 skilful are the divers in their movements, that they 

 scarcely touch the boat into which they fling their 

 prey before they dive again. When the boat was 

 filled it proceeded to the shore, and its place was sup- 



