THE COTTAGE GARDENER AND COUNTRY 
Tlie common Sea Urchin and the Starfish, which may bo seen on 
every coast, being the most familiar examples of the class. 
The Echinodermata arc very much more highly organised 
than the Polypes, and are nearly all of them free animals, creep¬ 
ing about at the bottom of the sea, by means of a peculiar 
arrangement of parts which will be hereafter explained. The 
larger numbers of them are protected by a leathery skin, which 
is additionally strengthened by calcareous plates or spines, and 
are in that manner distinguished from the Medusae, which, 
although equally free animals, are of a delicate and membranous 
texture. Most of the species are externally radiated, the lower 
groups resembling Polypes. The Feather Star, a very familiar 
specimen, is in its earlier stage of existence fixed to a stem ; but, 
on reaching maturity, becomes fixed and star-like. 
It is worthy of notice that a certain definite number seems to 
regulate the arrangement of parts in all the Radiata. In the 
Echinoderms that number appears to be five; in tlio words 
of Professor Forbes:—“In the Echinodermata the reigning 
number is five. The name of ‘ Five-fingers,’ commonly given by 
mariners to the Starfishes, is founded on a popular recognition 
of the number regnant. Among the lower and the typical orders 
we find this number regulating the number of parts. Every 
plate of the Sea Urchin is built up of pentagonal particles. The i 
skeletons of the digestive, the aquiferous, and the tegumentary 
systems, equally present the quinary arrangement, and even the i 
cartilaginous framework of the disc of every sucker is regulated 
by this mystic number. When the parts of Echinodermata j 
deviate from it, it is always either in consequence of the ! 
abortion of certain organs, or it is by a variation by representa- \ 
tion —that is to say, by the assumption of the regnant number of 
another class. Thus do monstrous Starfishes and Urchins often 
appear quadrate, and have then' parts fourfold, assuming the 
regnant number of the Actinodermata.” 
The Echinoderms differ materially in shape, usually, however, 
presenting a radiate arrangement of parts, and often perfectly 
resembling a star in form, as in the case of the common Star¬ 
fish. In the globular Sea Eggs, ( Cidaridce ), also the same 
asteroid formation may be observed ; hi others it seems to be 
almost undistinguishable, as in the Sea Cucumbers ( Holo - 
thuridai), although the tentacular crown which surrounds the 
anterior extremity of these animals is also of a radiate structure. 
We merely mention these creatures cursorily at present j but 
full descriptions of them will be given in then* due course and 
order. 
There is one ’very romarkable peculiarity displayed by some 
species of the Echinoderms—namely, a power of instantaneous 
dismemberment, which power enables them to indulge in sudden 
suicide, to which they have a singular tendency. This is noticed 
in the species called “ The Brittle Star.” A very amusing illus¬ 
tration of this strange propensity is given by Professor Forbes 
in his “ History of British Starfishes,” which we cannot do 
better than extract. 
“ The first time I ever took one of these creatures, I succeeded t 
in getting it into the boat entire ; and never having seen one be- , 
fore, and being quite unconscious of its suicidal powers, I spread it 
out on a rowing-bench, the better to admire its form and colours. 
On attempting to remove it for preservation, to my horror and 
disappointment I found only an assemblage of rejected members. 
My conservative endeavours were all neutralised by its destruc¬ 
tive exertions, and it is now badly represented in my cabinet by 
an armless disc, and a discless arm. Next time I went to dredge 
in the same spot, determined not to be cheated out of a speci¬ 
men in such a way a second time, I brought with me a bucket of 
cold fresh water, to winch article Starfishes have a great anti¬ 
pathy. As I expected, a Luidia ( Lingthorne) came up in the 
dredge, a most gorgeous specimen, as it does not generally break 
up before it is raised above the surface of the sea. Cautiously 
and anxiously I sunk my bucket to a level with the dredge’s 
mouth, and proceeded in the most gentle manner to introduce 
Luidia to the purer element Whether the cold air was too much 
for him, or the sight of the bucket too terrific, I know not; but 
in a moment he proceeded to dissolve his corporation, and at 
every mesh of the dredge his fragments were seen escaping. In 
despair I grasped at the largest, and brought up the extremity 
of an arm, with its terminating eye, the spinous eyelid of which 
opened and closed with something exceedingly iike a wink of 
derision.” 
The existence of a nervous system in Echinoderms has been 
admitted, and consists of a series of ganglia or nerve-knots sur¬ 
rounding the gullet, united by a nervous ring, and giving off a 
GENTLEMAN, August 28, 1860. 309 
set of nerves to every ray of the body. The soxes are invariably 
separate, in contradistinction to the rule which prevails in the 
lower Radiata. 
Some of those animals are eatable. The Sea Urchin, for 
instance, often forms an article of food for the poorer inliabit- 
ants of France, Spain, and Italy; and the Trepang of commerce, 
which is a species of Holuthuria (Sea Cucumber or Sea Slug) 
dried forms an article of luxury at the table of that highly-refined 
people the Chinese.—W. 
(To be continued .) 
THE GEEAT AMERICAN ALOE. 
The flowering of this plant (Agave americana) in Eng¬ 
land is a remarkable event;—“like angels’ visits, few and far 
between. . At Leeds, in Yorkshire, there is a large garden ori¬ 
ginally laid out as a Botanical Garden, but from some cause or 
other it has ceased to bear that character, and now belongs to a 
private gentleman. Some of the old greenhouses are yet stand¬ 
ing, and in one.of them some years ago a large specimen of this 
Aloe was planted out in a pit, in which it now grows, and is 
flowering. It is, perhaps, the largest plant of the kind in 
Europe, as the following dimensions will show. It has ninety- 
six leaves, the largest is 7 feet long, 15 inches broad, and 
4|- inches thick. Many of the others are very nearly of the 
same gigantic size. The main body of the plant, just below 
where the flower-stem springs up, is 6 feet in circumference, and 
the entire plant covers a space of 60 feet in circumference. The 
flower-stem, 8 feet from the plant, is 12 inches round, and 20 feet 
high. It is expected before the flowers are fully expanded that 
it will reach the altitude of 30 feet. It has twenty-three panicles 
of flower-buds, and it is supposed there will be 3000 blooms on 
this immense plant. 
In order that the public may have an opportunity of seeing 
this noble plant, the owner has let the gardens for its season of 
blooming to Mr. T. Dawkins Appleby,'the son of our esteemed 
contributor. 
In the garden there are many specimens of rare trees and 
shrubs now in good health, and of a goodly size. 
Altogether a visit to see the Aloe and to have a walk in those 
gardens is a treat to all lovers of gardening scenes.. The Aloe is 
expected to be in its best state about the first week in September, 
and will last in bloom through the whole of that month. 
GREENHOUSE ORCHIDS. 
(Continued from, page 318.) 
Insects. —In a cool moderate temperature Orchids are not 
generally infested with insects. Sometimes, however, they appear, 
and should be instantly destroyed in order to prevent their 
increase. The insects that prevail most on them are the black 
thrips, the white scale, the cockroach, the slug, and red spider— 
all bad enough when they prevail to any extent. 
The thrips not only feeds upon the leaves, but exudes a glutin¬ 
ous liquor, which stops up the pores of the leaves; which, to¬ 
gether with the swelling out of the sap, causes the leaves to 
become blotched, gangrenous, and finally to perish. Frequent 
smokings with tobacco will destroy the living insects, also a 
dredging with Scotch snuff is a good agent for destroying them ; 
but keeping the plants healthy and frequent spongings will 
generally banish this pest. 
White Scale. —This insect is often found in large numbers on 
imported Orchids. The far-famed Gishurst Compound is the 
best destroying agent I have seen yet applied. I have, however, 
cleared plants of the scale by a mixture of sulphur, soft soap, 
and tobacco water. 
Cockroaches arrive in this country amongst imported Orchids, 
both in the egg state and alive. There are many remedies adver¬ 
tised. Chase’s Beetle Poison is as good as any. I have thinned 
the numbers of them by placing a glass vessel half full of sweet¬ 
ened beer in their tracks, and by searching for them in dark 
nights with a bull’s-eye lantern, and with a pronged fork impaling 
them, or killing them with a fiat piece of wood. I have been 
dreadfully annoyed in some mornings to find a nice young root 
eaten away, or a promising flower-shoot, half gnawed through, by 
these insects ; and so will every grower of Orchids, unless he 
wages war with them continually. So also with the white slug, 
or any other species of that ilk. In moist houses they can travel 
