396 Acaleph^. RADIATA Acalephs. 
but instead of being inclosed in a shelly case, their skin 
are a great many species and varieties now known, 
is only hardened with irregular scale-like or oblong 
though formerly they were all described under one, viz.. 
calcareous plates. The body is more or less elongated 
Holothuria edulis. These animals are all natives of 
and cylindrical, sometimes vermiform, soft or flexible 
the Indian and Australian seas, and are well known 
in all its parts, very extensile and contractile, and fur- 
under the general name of Trepang, Tripang, Biche-de- 
* 
nished with numerous suckers, by means of which their 
mer, or Beche-de-mar. They are generallyfound adher- 
movements are effected. They have a large orifice at 
ing to rocks near the shore. Some of them attain a 
each extremity, at the anterior end of which is situated 
'considerable size, reaching to nearly the length of two 
the mouth, placed at the bottom of a kind of funnel, 
feet, and the circumference of seven or eight inches. 
which is surrounded, or supported throughout its whole 
These animals are much esteemed by the Chinese as a 
circumference, by a circle of small calcareous fibres, 
nutritious article of food, and are particularly used for 
and crowned with a circle of from five to ten branchial 
flavouring their soup. They form an important article 
appendages more or less plumose. These the animal 
of commerce amongst the natives of the islands of the 
can at pleasure retract entirely. The reproductive 
Indian archipelago. Cochin China, the islands belong- 
organs are situated near the mouth, and each animal 
ing to Australia, &c. Thousands of Malay proas are 
is bisexual. At the extremity opposite to the mouth 
annually engaged in this fishery, and the produce taken 
there is situated the respiratory organ or gill, which is 
to Canton is sold at an average for about forty-five 
in the shape of a hollow tree very much branched, and 
Spanish dollars per picul (= 133J lbs). Macassar is 
the animal can receive or expel water by means of this 
tlie head quarters for this fisher}', and about 8,333 cwt. 
apparatus, which possibly thus assists it in its locomo- 
are annually exported from thence to Canton. There 
tion, as well as supplies air from the inhaled water. 
are two principal kinds of Trepang sold in Canton. 
These animals are, like the leeches amongst the Anne- 
“ The black, called coatoo, is sold to the Chinese for 
lides, exceedingly sensitive, and when disturbed will 
forty dollars the picul ; the white or grey, called koj'o, 
sometimes contract so violently that the integuments 
is worth no more than twenty.” Though the natives 
are ruptured and the intestines protrude. The Hole- 
of the Celestial Empire are very partial to the Trepang 
thurioids are generally distributed through the seas of 
as an article of food, Europeans do not share in their 
the globe, but are congregated in the greatest numbers 
taste. 
in the Eastern seas. “ On our shores,” says Professor 
Forbes, “they are rare and unattractive animals, but 
Order V.— SIPUNCULOIDEA (Siphon-worms). 
abroad they are very abundant.” Those of the Euro- 
The order Sipunculoidea is characterized by the 
pean seas are never highly coloured, but in more tropical 
animals having a coriaceous covering, free from any 
ones, where coral reefs rise within a moderate distance 
calcareous bodies. The mouth, or commencement of 
of the surface, as in the Red Sea and the seas to the 
the oesophagus, is not surrounded by calcareous fibres. 
north and east of Australia, they are many of them 
and the form of the body is eylindrical. 
splendidly coloured. The general form of the Hole- 
The family Sipunculida: is represented by the genus 
thuriae is that of a cucumber, and many of the species 
Sipunculus, whicli has the anterior part of the body or 
are of a gelatinous nature and esculent. 
neck retractile and exsertile. At the extremity of this 
The species belonging to this order are numerous. 
retractile neck is placed the mouth, which is of an 
and are arranged in several groups or families. 
orbicular form, and from which is protruded a retractile 
The True Holothurians (Sea-cucumbers or Sea-slugs) 
proboscis surrounded with linear tentacles. The vent 
have a rather soft, somewhat elongated, subcylindrical 
is situated at the side near the anterior third of the 
body, covered throughout with tentaculiform suckers. 
length of the most swollen part of the body. 
which in the genus Holothuria form regular lines from 
The SipuncuU live in the sand of the sea-shore near 
the mouth to the vent. 
high water mark, or amongst the debris of broken shells. 
THE NIGGER OR COTTON SPINNER {Holothuria 
Their food appears to consist of the mud of the shore. 
mgra) is the only species of the genus Holothuria that 
mixed up with organic particles. A considerable num- 
is found in Great Britain. It is taken in the Cornish 
ber of species have been described, and not fewer than 
seas in deep water, and is held in great detestation by 
ten have been found on the British coasts. Some of 
the fishermen on that coast. 
the species perforate submarine rocks and lodge in the 
Genus Trepang. — The genus Trcpang, containing 
cavities so made, or take possession of old shells, like 
several edible species, belongs to this family. There 
the hermit crabs. 
Class II.— The SEA NETTLES or ACALEPHS (Acalephj!). 
The Sea-nettles, or Acalephs, form a class of interest- 
productions of the intestines, hollowed in the substance 
ing creatures of beautiful structure and appearance. 
of the body. This body is composed of a transpai-ent 
which, however, to be fully understood, must be studied 
gelatinous substance formed of polyhedral ceils, and 
on the spot where they are found. As Cuvier defines 
there is only in a few to be seen any calcareous or 
them, they are animals which are found swimming in 
cartilaginous nucleus that can be compared to a rudi- 
the sea, and in whose organization may be perceived 
mentary skeleton. The quantity, indeed, of solid mat- 
vessels, which in truth are most frequently nothing but 
ter in them is so small, that if wo take a Medusa (for 
