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surface of the body has the mouth in the centre, and from it deep grooves radiate to the ends of the arms. At the bottom of each groove is a See also:

WATER

water-See also:

VESSEL (O. Fr. vaissel, from a rare Lat. vascellum, dim. of vas, vase, urn)

vessel, which gives off branches to the podia or sucking-feet on each See also:

side of it. A See also:

section across this groove is given in the See also:

ARTICLE (from Lat. articulus, a joint)

article ECHrNODERMA, fig. 12 B. The arrange- ment and working of this FIG. 2.—A sterias rubens, under surface. See also:

HYDRAULIC

hydraulic See also:

SYSTEM

system is a, The See also:

ARM (a common Teutonic word; the Indo-European root is ar, to join or fit; cf. the Lat. armus, shoulder, and the plural word arma, weapons, Gr. apphs, joint, and the reduplicated apapilKSV, to join)

arm-groove with its See also:

ROW, JOHN (c. 1525—1580)

row of sucking- essentiallY the same as feet or podia. b, End of a See also:

PODIUM (Gr. lr66tov, diminutive of ?roils, foot)

podium, magnified. in the See also:

sea-urchin, except for the presence of plates at the bottom of the groove beneath the radial water-vessel, and the See also:

ABSENCE (Lat. absentia)

absence of any plates covering the groove.

At the end of each See also:

ray is, as in the urchin, a single tentacle surrounded by pigment and connected with a definite plate called " terminal." Thus the terminals of a See also:

STARFISH

starfish correspond to the oculars of a sea-urchin (see ECII1NODERMA, fig. 3). The See also:

STOMACH (Gr. vrbsaxos from arbga, a mouth)

stomach is not a See also:

long coil, but a See also:

SIMPLE

simple See also:

sac with branched See also:

BLIND, MATHILDE (1841—1896)

blind tubes extending into each ray. A generative gland also passes down the side of each ray, and emits the milt or eggs when ripe through a See also:

PORE

pore near the body. Spawning takes See also:

PLACE (through Fr. from Lat. platea, street; Gr. IrAar6s, wide)

place in See also:

SPRING (from " to spring," " to leap or jump up," " burst out," O. Eng., springau, a common Teut. word, cf. Ger. springer, possibly allied to Gr. QnrFpxecOac, to move rapidly)

spring or See also:

early summer. A starfish can crawl in any direction by means of its sucking-feet, whether the surface be hard or rough or polished, or the softest silt, whilst its supple body can squeeze through incredibly, narrow crevices. The See also:

RATE

rate of progress is about six inches a minute. The, starfish are the scavengers of the sea, but unfortunately do not confine their attentions to decaying See also:

MATTER

matter; they eat oysters, clams, mussels, barnacles, sea-snails, See also:

WORMS

worms, See also:

CRUSTACEA

crustacea and even smaller starfish. There is See also:

CONSTANT, BENJAMIN (1845-1902)

constant See also:

war between See also:

OYSTER

oyster-fishers and starfish; no less than 42,000 bushels of starfish were removed from the oyster-beds of See also:

CONNECTICUT

Connecticut in a single See also:

YEAR

year, but not till they had worked damage to the amount of $631,500. The simplest way in which a starfish eats is by taking small bits of See also:

food into the stomach, and ejecting the refuse again through the mouth. But since the mouth is quite small and the food often large, the starfish finds it more convenient to turn its stomach inside out and to wrap it around the See also:

animal to be eaten, which is then digested quietly and the stomach withdrawn again. In the See also:

case of oysters and similar bivalves, the starfish first has to open them; and this it does by fixing the suckers of one or two rays to one See also:

VALVE (Lat. valva, a leaf of a double or folding door, allied to volvere, to roll, as of a door on its hinges)

valve and those of the opposite rays tb the other valve, while it may get a See also:

PURCHASE

purchase by also holding on to some neighbouring See also:

OBJECT

object.

It then begins to straighten out its rays. The oyster can withstand a very strong pull, but it cannot hold out against a long pull, and the starfish does not See also:

HURRY (or URRV), SIR JOHN (d. 165o)

hurry. At last the oyster gives way, and the starfish has its See also:

REWARD

reward; but its companions often join in, and you may see a whole See also:

ball of them interlaced See also:

ROUND (O. Fr. rond, Lat. rotundus, the Fr. is the source also of Du. rond; Ger., Swed., Dan. and Nor. rond)

round See also:

HALF

half-digested molluscs and See also:

ROLLING

rolling about. Starfish begin to eat voraciously when quite See also:

young; one less than gth in. across has been observed to eat over fifty young clams of half that length in six days. The more a starfish has to eat the quicker it grows, and it may become sexually mature in less than a year, then producing many thousands of young. Fortunately the increase is kept in check by many causes. The young, while still in the See also:

STAGE (Fr. 6/age; from Lat. stare, to stand)

stage of See also:

FREE

free-See also:

SWIMMING (from " swim," A.S. swimman, the root being common in Teutonic languages)

swimming larvae, are swallowed in millions by various fish. When they See also:

settle down on seaweed their See also:

bright See also:

COLOURS, MILITARY

colours attract eels and many small fishes. Later in See also:

LIFE

life they are attacked by parasites, while those which stray into shallow water are eaten by gulls and crows. Freshets and See also:

COLD (in O. Eng. cald and ceald, a word coming ultimately from a root cognate with the Lat. gelu, gelidus, and common in the Teutonic languages, which usually have two distinct forms for the substantive and the adjective, cf. Ger. Kolte, kalt, Dutch koude

cold currents are also destructive. Probably the best way in which See also:

man can keep down the See also:

numbers of starfish is by dredging the seaweed in the latter half of See also:

JULY

July when it is covered with young; a singlecartload thrown on See also:

SHORE

shore would See also:

CAPTURE (from Lat. capere, to take; Fr. prise maritime; Ger. Wegnahme)

capture many. millions. At a later stage tangles of See also:

HEMP (in O. Eng. henep, cf. Dutch hennep, Ger. Hanf , cognate with Gr. Kavval3er, Lat. cannabis)

hemp or See also:

cotton See also:

WASTE (O. Fr. wast, guast, gast, gaste; Lat. vastus, vast, desolate)

waste may, be dragged over the oyyster-beds, when the starfish will cling to them by their pedicellariae.

They make excellent manure, but are of ne further service to man. Fishermen who catch them in their nets or on their lines often See also:

TEAR

tear them in half and throw them back into the sea. Some of these mutilated upper surface. a, Madreporite. d, The same magnified. b, Anus. This starfish may be 9-12 in. across. See also:

SPECIES

species A. forbesi and A. vulgaris. The animal consists of a central body or disk, produced into five arms or rays. The upper surface is covered with a' leathery skin, strengthened by a See also:

RAFTER

rafter-See also:

WORK

work of little bones or plates, made of crystalline carbonate of See also:

lime, many of them bearing prickles of the same substance and small pincer-like bodies—the pedicellariae (see SEA-URCHIN). In the animals may, however, grow fresh rays, and thus one may find a starfish consisting of one large ray and four quite small ones, the whole shaped like a See also:

COMET (Gr. Koµieiis, long-haired)

comet. The Ophiurids (the name means " snake-tails ") include the brittle-stabs, See also:

sand-stars, and See also:

BASKET

basket-fish or See also:

MEDUSA

medusa-heads. The two former, which may often be found hiding under the rocks, or in the seaweed, or in pools at See also:

low See also:

TIDE (O. Eng. lid, cf. Ger. Zeit, time or season, connected with root of Sanskrit a-diti, endless)

tide, resemble the See also:

ORDINARY (med. Lat. ordinarius, Fr. ordinaire)

ordinary starfish in having five distinct arms.

These, however, as shown in fig. 3, are long and See also:

SERPENT (Lat. serpens, creeping, from serpere; cf. "reptile " from repere, Gr.4 ml-eta)

serpent-like, and are attached to a relatively small body or disk. The See also:

DIGESTIVE

digestive and generative systems do not extend to the rays but are confined to the body. The arms are cylindrical and have no groove on the under side such as exists in starfish; but the water-vessel traverses the solid bones that See also:

FORM (Lat. forma)

form the See also:

AXIS (Lat. for " axle ")

axis of the arm, and the podia pass out through See also:

SPECIAL

special openings (see See also:

ECHINODERMA

ECHINODERMA, fig. 18). In Ophiurids it is the arms that are used for locomotion and not the podia, so that the latter have no terminal suckers. The axial ossicles, which correspond to the plates flooring the arm-groove in a starfish, resemble vertebrae connected by pairs of straight See also:

MUSCULAR

muscular bundles, and articulated by tenon-and-See also:

MORTISE, or MORTICE (adapted from the Fr. mortaise; cf. Ital. mortise and Spanish mortaja; the origin is unknown; Celtic equivalents, such as Gaelic moirteis, are of French origin)

mortise See also:

JOINTS

joints, according to whose degree of development the arms vary in their See also:

POWER [WILLIAM GRATTAN] TYRONE (1797-1841)

power of coiling. These vertebrae are encased in the tough See also:

OUTER

outer skin of the arm, in which are See also:

DEVELOPED

developed plates. Spines See also:

BORNE, KARL LUDWIG (1786–1837)

borne by these plates aid the animal in locomotion. The skin of the disk also bears small plates, which are often covered with prickles. The mouth is on the under surface of the disk, and round it are a number of See also:

SHORT, FRANCIS JOB (1857– )

short, See also:

FLAT (a modification of O. Eng. flet, an obsolete word of Teutonic origin, meaning the ground beneath the feet)

flat processes, the mouth-papillae, which serve as strainers. Inside the mouth are seen the five tooth-plates, borne on a strong See also:

FRAME

frame of complicated structure.

In the sand-stars the rays are comparatively short, with their spines closely pressed to their sides, so that they look like lizards' tails; in the brittle-stars the rays are much longer and more flexible, with the spines See also:

STANDING

standing out, so that they look like wriggling centipedes attached round a little sea-urchin. The brittle-stars are more active than the sand-stars, and can go more than two yards in a minute; some of them, if seized, break off their arms, which continue breaking into smaller pieces; but the body can soon grow new ones. Sand-stars and brittle-stars are found in all seas, usually occurring in quantities, but are most abundant in the See also:

rock-pools of the tropics. By constantly sweeping their arms over the sea bottom, they gather food consisting of minute animals. They eat the bait of fishermen, and their fish as well if they find any already dead, but they are themselves a favourite food with many fish, notably the See also:

cod. The basket-fish or medusa-heads are Ophiurids whose arms See also:

BRANCH (from the Fr. branche, late Lat. branca, an animal's paw)

branch several times, their ends often See also:

curling and interlacing. They live in deeper water and are often brought up clinging to fishermen's lines. The See also:

FEATHER (0. Eng. (ether, Ger. Feder, from an Indo-European root seen also in Gr. lrrepov, and aEreo-Oat, to fly)

feather-stars (fig. 4) have a central body and five arms, each forking at least once and fringed with small branches (pinnules) which give the feathery See also:

APPEARANCE (from Lat. apparere, to appear)

appearance. The mouth is in the middle of the body, and from it grooves pass along the arms and all their branches. The animal lives with the mouth upwards, and although it can crawl and even swim by See also:

MOVEMENT

movement of its arms, it generally fixes itself to a' See also:

stone or seaweed or some zoophyte, by means of a bunch of small jointed and hooked processes (cirri) growing from the back or under side of the body. It gets its food in this way: the arm-grooves (ECHINODERMA, fig.

12, C) are lined with minute hairs (See also:

CILIA (plural of Lat. cilium, eyelash)

cilia) always waving in the direction of the mouth, towards which they drive a stream of water; this stream, containing minuteorganisms, constantly flows through the coiled gut, which extracts nourishment from it. The feather-stars were formerly placed with the starfish, but they really belong to another class of Echinoderms—the Crinoidea. In 1823 J. V. See also:

Thompson, of See also:

Cork, discovered that the feather-star when quite young was fixed by a stalk, just as are nearly all crinoids (see ECHINODERMA, figs. I and 2). The stalked crinoids are not so numerous as they once were, but feather-stars belonging to about half a dozen genera (Antedon, Actinometra, &c.) See also:

ACE (derived through the Lat. as, from the Tarentine form of the Gr. etc)

ace found in all seas at all depths, often in enormous numbers. (F. A.

End of Article: DERMA

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