Childrens Illustrated Encyclopedia

391

Sea creatureS, Such aS the octopuS and squid, have always held a

strange fascination for humans. With their powerful tentacles and strange

shape, they were once thought of as sea monsters. octopuses and squid are

clever, active creatures, the biggest and most intelligent of all the invertebrates

(animals without backbones). they have sharp eyesight, a large brain,

fast reactions, and the ability to remember. octopuses, squid, and

their relatives, the cuttlefish, are mollusks, related to shelled

animals with soft bodies, such as snails and clams. unlike snails and

clams, octopuses, squid, and cuttlefish have no outer shells, though

squid have a very thin shell called a pen inside the body. the

white oval cuttlebones of cuttlefish are often seen

washed up on beaches. an octopus has eight

“arms” covered with suckers, which it uses for

moving around. Squid and cuttlefish have

eight short “arms” and two

long tentacles which curl

and uncurl. they use

their arms as rudders

for swimming and their

tentacles for

catching prey.

Octopuses and squid

Ink

cloud

octopuses

and squid have

an ink gland attached

to the digestive system.

to confuse an enemy,

they squirt ink out

of the siphon and

cannot be seen behind

the dark, watery screen.

this ink was once used by

artists and is called sepia,

which is also the scientific

name for cuttlefish.

cuttlefISh

octopuses, squid, and

cuttlefish can change color

in less than a second. this

can provide camouflage so

that the creature blends in

with the surroundings. It

may also indicate a change

of mood—a male cuttlefish

turns black with rage when

it is angry. the dappled red

coloring of the cuttlefish

shown here is a good disguise

among the coral.

SquId

With its torpedo shape, the

common squid is an especially

fast swimmer. powerful muscles

inside the body squirt water rapidly

through the siphon, pushing the

creature along through the water.

Common squid

Giant squid

Measuring 60 ft (20 m) in length including its tentacles,

the giant squid is the world’s largest invertebrate. It

is an important source of

food for sperm whales.

coMMon octopuS

the common octopus lurks in

caves or crevices during the day.

It emerges at night to hunt for

crabs, shellfish, and small fish.

It has a hard, beaklike mouth

and a rough tongue.

Some large octopuses

measure 30 ft (9 m) across

with their “arms” spread out.

However, stories of giant

octopuses that swallow

divers whole are untrue.

Water can be

squirted out

through siphon

for jet-propelled

movement.

Mouth is on underside;

it has a horny “beak”

for cutting food,

and saliva that

contains poison.

Each “arm” has two rows of

powerful suckers for moving,

feeling, and grabbing prey.

Find out more

animals

deep-sea wildlife

ocean wildlife

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