stored water keeps them alive during
dry periods. Unlike many plants, cacti
do not have deep roots. Instead they
have roots that spread out near the
surface of the soil. This is important to
their survival. These roots absorb water
from a wide area during the few times
it rains.
Cacti are known for their pointy spines.
These grow in different patterns on the
plant’s surface. Some cacti also have
flowers and branches. Most do not have
leaves. If a cactus has leaves, they are
very small and fall off as the plant grows.
Cacti come in many sizes. The cactus
called the prickly pear grows in low
bunches. The giant cactus known as the
saguaro can be 50 feet (15 meters) tall.
Its branches may be 2 feet (about 0.6
meter) thick.
Most cacti grow in the ground. Some
cacti, known as epiphytes, grow on
plants. Others may grow on hard things
such as rocks.
Uses
Cacti are often grown for decoration.
Many unusual and beautiful varieties are
prized as houseplants. In South America
cacti are sometimes used as fences. The
U.S. state of Arizona has adopted the
saguaro as its state flower.
Some types of cacti are also grown for
food. The egg-shaped fruit of the
saguaro can be eaten. People also eat the
fruit of the prickly pear.
Caddo
The Caddo were a group of about 25
Native American tribes that originally
lived in the area that is now the U.S.
states of Louisiana, Texas, Arkansas, and
A type of cactus known as the Engelmann
prickly pear commonly grows in the southwestern
United States.
6 Caddo BRITANNICA STUDENT ENCYCLOPEDIA
Oklahoma. They built their villages on
fertile lands along the Red River.
The Caddo got most of their food by
farming. They grew corn, pumpkins,
squash, and beans. They also used bows
and arrows to hunt deer, bear, and small
game animals. They lived in domeshaped
houses made from grass stuffed
into a wooden frame.
In the 1540s the Caddo welcomed
Spanish explorers into their territory.
Spanish and French traders visited regularly
by the early 1700s. The Caddo
traded their corn to other tribes for animal
furs. They then gave the furs to the
French in exchange for European goods.
As more and more non-Indians arrived,
the Caddo began to lose their lands. By
the mid-1800s they fled to Indian Territory
(now Oklahoma). There they
settled on a reservation along the
Washita River, which they shared with
theWichita Indians.
By the end of the 20th century, there
were about 3,000 Caddo in the United
States. Many lived in tribal lands in
Oklahoma.
#More to explore
Native Americans
Caesar, Julius
The general and dictator Julius Caesar
helped to build ancient Rome into a
mighty empire. The name Caesar
became the Russian word tsar and the
German kaiser. Both mean “emperor.”
Julius Caesar was born on July 12 or 13,
in about 100 BC. His father died when
Caesar was 16. Caesar’s family was patri-
The Caddo people made this small human
figure in the early 1800s.
Julius Caesar was a leader of ancient
Rome. He built a mighty empire. This
marble bust of Caesar is in the Capitoline
Museum in Rome.
BRITANNICA STUDENT ENCYCLOPEDIA Caesar, Julius 7
cian, or upper class, but they supported
the common people in politics.
Rise to Power
Caesar studied public speaking and later
entered politics. In 59 BC he was elected
consul, the highest public office in
ancient Rome. As one of two consuls, he
ruled the Roman state for one year.
He then left Rome to govern a Roman
province in Gaul (modern France). In
nine years of fighting he brought all of
Gaul under Roman rule.
Dictator of Rome
Caesar returned to Italy in January of 49
BC and made himself dictator. Five years
of civil war between Caesar’s forces and
the supporters of the popular general
Pompey followed. Pompey fled to Egypt
and died there before Caesar could catch
him. But Caesar continued to fight and
win battles against Pompey’s supporters.
When he returned to Rome, Caesar
pardoned his old enemies and gained
many supporters. Not everyone trusted
Caesar, however. Many wanted Rome to
be a republic governed by a group of
people rather than a dictatorship led by
one man alone.
Sixty senators agreed to a plan to kill
Caesar onMarch 15 (the “Ides of
March” in the Roman calendar), 44 BC.
Among them was Caesar’s friendMarcus
Junius Brutus. As he died, Caesar said,
“Et tu, Brute?” (“You too, Brutus?”).
..More to explore
Augustus • Dictator • Rome, Ancient
Cairo
Population
(2006
estimate), city,
6,759,000;
(2005
estimate), urban
area,
11,128,000
Cairo is the capital of Egypt, a country
in northeastern Africa. It is the largest
city in Africa. Cairo has long been the
cultural center of the Arab world.
Places of Interest
Two areas, new and old, make up Cairo.
Modern Cairo faces the Nile River. It
includes the central business district and
newer living areas.
In Cairo’s oldest areas many people live
in crowded conditions. Many ancient
monuments are found there. The City
of the Dead is a large section of historic
cemeteries along the edge of the city.
Thousands of poor people live among
the tombs there. The Great Pyramids at
Giza lie along the outskirts of Cairo.
Economy
Cairo has long been an important trading
center. Factories in the city make
