62 
Class III. 
The Corals have always been among the most 
famous productions of the sea, but it was long be- 
fore it was known that the costly and beautiful red 
coral, as well as the numerous white corals which 
form great reefs in the tropical seas, were animal 
productions, and closely allied to the low forms of 
iife, without a skeleton, called Sea Anemones. Both 
consist of a hollow cavity, but in the corals, this is 
divided into a number of vertical partitions by 
numerous walls of separation. 
The mouth, or opening to the body-cavity, is 
surrounded by tentacles, equal in number to the 
partition-walls; and these tentacles are well provided 
with urticating organs. 
Most of the coral animals form colonies of 
various forms by budding. Channels penetrating the 
mass in which the separate animals are embedded, 
unite all the animals of the colony, so that the 
nourishment taken by one animal feeds the common 
Order I. 
These have 8 ciliated tentacles, and as many 
partition layers. The animals found colonies, which 
usually contain an axial skeleton of horny or cal- 
careous matter. The skeleton is often limited to a 
slight calcareous deposit in the integument of the 
colony. 
Plate XXX. fig. e. Alcyonium palmatum, the 
Dead Man's Fingers, forms fixed colonies with no 
axial skeleton, of leathery consistence, and with slight 
calcareous deposits of a determinate form. 
Fig. f. Fennatula phosphorea, the Sea-Pen, has 
a horny yielding axial skeleton, with the lower 
end fixed in the sand or mud at the sea-bottom. 
The colony has the shape of a feather, and the 
separate animals are placed on its side-branches. 
It is a luminous animal. 
Fig. g. Umbellula encrinus is a species found 
at a great depth in the Northern Seas. It has a long 
stem, at the upper end of which the animals are 
arranged in such a manner that the whole has some- 
what of the appearance of a magnificent dandelion, 
swaying on a slender stalk. 
Fig. h. Renilla violacea is a small and incon- 
spicuous colony in comparison to the last, but the 
contrast between the blue kidney-shaped stem and 
the yellow animals planted on it give it a pretty 
appearance. 
Fig. i. Gorgonia flabellum is called from its 
shape Venus’s Fan. We have figured only the 
Order Il. 
In these animals, the tentacles are either six in 
number, or a multiple of six; and in the latter case 
they are arranged in a series of separate rows. 
They are divided into two sharply defined Suborders. 
Suborder I. Actinaria. 
In the Sea-Anemones there is no calcareous 
skeleton. They are generally separate animals of 
considerable size and bright colours, and can creep 
slowly from place to place by means of a retractile 
foot. 
They are richly provided with urticating cap- | 
Anthozoa. 
stock. The animals are called polyps, but the 
colony produced by the budding and branching of 
the animals, and on which they are fixed, is called 
the Polypidom or Polyparium. It rarely remains soft, 
but usually forms a skeleton of vary various form, 
which may be so massive as to form a firm rocky 
core, with only a thin layer of animal matter on the 
surface, or scattered through it. When the animals 
die, this substance, which is usually of a shining 
white colour, retains the exact form of the colony. 
In other cases the polyparium is horny, or contains 
but few calcareous layers. The coral-animals which 
form no colonies, are usually quite fleshy, and with 
out skeleton. The coral-animals multiply by eggs 
as well as by budding. From the eggs a freely- 
swimming larva is produced, which does not fix its- 
self for some time. All the corals are marine, and 
they are classified by the number of tentacles. 

Octactinia. 
skeleton, and not the animals. [t comes from the 
West Indies. In this and the allied species, the 
horny or calcareous tree-like or fan-like skeleton is 
covered with a thin crust which is easily rubbed off. 
Vig. k. Corallum rubrum. The Red Coral has 
always been highly esteemed. .The colonies form 
large branching stems with a red axis as hard as 
stone, which is covered with a red porous layer, 
easily removed, containing isolated calcareous par- 
ticles. The separate animals are all connected by 
the pores, and have the appearance of shining white 
stars on the red stem; but as soon as they are 
touched, they withdraw their tentacles, and disappear. 
The young animals are small wormlike ciliated crea- 
tures, which swim freely about for a time. The 
Red Coral is found only in the Mediterranean Sea 
The coral fishery, in which 300 vessels are annually 
engaged, and which yields a clear profit of upwards 
of £100,000, is carried on chiefly on the coasts of 
Algeria and Tunis. The corals, which live at the 
depth of from fifteen to eighty fathoms, are torn away 
and brought to the surface by specially constructed 
nets. The price of the raw material varies from 
ten shillings to £10 per pound according to the size 
and colour. 
Fig. 1. Zudbtpora purpurea is found in the Red 
| Sea, and has also a very solid red skeleton Here, 
however, the separate individuals are arranged in 
parallel tubes connected by horizontal plates, so that 
the whole is not unlike the pipes of an organ, 

Hexactinia. 
sules, and feed on small fish, crustacea, &c In 
captivity they are fed with fragments of meat. The 
numerous tentacles which surround the mouth are 
reproduced if cut off, and if an animal is cut in two, 
two new ones are formed. 
Plate XXX. fig. m Sagartia rcsea has bright 
red tentacles spotted with white. 
Fig. n. Anthea cereus, the Opelet, is remarkable 
for its beautiful green colour, and numerous tentacles 
(about 180), which are estimated to be armed with 
from 6,000 to 7,000 millions of urticating capsules. 

