A network of caves containing several hundred pristine prehistoric wall paintings and engravings dating from the ice age has been discovered in southern France, French Minister of Culture Jacques Toubon announced today.

Toubon said the images, believed to be as many as 20,000 years old, represent a major find in the field of prehistoric art. "Naturally, for us who are not specialists, and of course for archaeologists and historians, it is a discovery with an exceptional interest," he said.

The 300 wall paintings and engravings of mammoths, reindeer, bison, rhinoceroses, panthers, horses and bears are in perfect condition. Although they have not been scientifically dated, Jean Clottes, a French government specialist in cave art, estimated that they are between 17,000 and 20,000 years old.

Clottes compared the discovery to the world-famous caves of Lascaux in Dordogne, because although these paintings are smaller, they contain so many diverse and impressive images. "Often in prehistoric art, animals are static," said Clottes. "Here they are presented in action." Horses are running. Rhinoceroses are butting horns. "There's a panel with only one giant rhino and good perspective," he said. "And there is the only representation of a panther we have in prehistoric art."

"It's very, very exciting," said Alexander Marshack, a research associate in prehistoric archaeology at Harvard University's Peabody Museum. He added that since the first ice age cave paintings were discovered in Europe in the late 19th century, "there have been major discoveries every couple of decades."

Unlike the art at Lascaux, which was found in 1940 and includes multicolored wall paintings, the newly discovered paintings are in hematite red pigment and charcoal. "I have the impression that it's the same hand or the same school," said Clottes, adding that the artists "used the technique of stump painting: spreading black paint to get depth, color and shading."

In the red paintings, the bear dominates, followed by mammoths, horses, rhinos and wild cats. Many of the images are of several animals together, sometimes superimposed upon one another. On one big panel, there are several bears, each with the front of the body speckled, followed by an ibex and two mammoths. Another ensemble, showing a horse, a mammoth and an owl, appears on the top of a 35-foot-high vault. In another, there is an enormous rhino with a disproportionate horn, followed by several other animals, traces of human hands and a sign composed of two semicircles.

In the black drawings, rhinos are abundant. In the engravings, there are mostly mammoths. The proportions of most of the animals are lifelike, with precise anatomic details. Human hands are depicted both in positive line drawings and negative silhouettes. There are more than 50 decorated surfaces in all.

The caves, named Vallon-Pont-d'Arc after a nearby town at the entrance of the gorge in the Ardeche region northwest of Avignon, were discovered Dec. 18 by a government archaeological official who, during a survey of the region's prehistoric sites, felt a current of air coming through a pile of rocks.

"We dug, cleared the path, and there was a 21-foot-deep well" that gave access to some underground chambers, said the official, Jean-Marie Chauvet. Examining the chambers, Chauvet noticed the type of red pigment sometimes found in cave art. He explored farther and came upon a network of galleries averaging 12 by 15 feet, with some as large as 120 by 210 feet, containing the paintings and engravings.

In fact, the tunnel served as a chimney to the galleries, Clottes said. The original entrance had long been sealed off naturally.

On the ground were traces of fires, pieces of flint and burned torches. Archaeologists found the bones of more than 100 bears, some of them arranged in a way suggesting they may have been used in rituals. For example, Clottes said, a bear skull was found on a rock in the center of a room.

The Peabody's Marshack said that more than 200 caves containing paintings or engravings have been found in a mountainous area called the Franco-Cantabrian region, which runs from northwestern Spain to southwestern France. He said the limestone mountains are riddled with caverns.

He said the earliest cave images date from about 27,000 years ago and the latest from about 10,000 years ago. "There was an explosion of art during the ice age of Europe," he added. The climate was colder and drier than it is now, and the region was mostly open steppes where large mammals roamed.

Marshack said the ice age images are usually found deep inside caves, and many archaeologists have suggested they had magical or ritual significance. The Stone Age people of the region did not live in caves, although they may have used cave mouths for shelter, Marshack said.

When Europe's climate began to warm and the steppes gave way to forests, about 10,000 years ago, the tradition of cave art came to an end. Archaeologists theorize that changes in the number and type of animals in the region led to human migrations and cultural changes.

Although the cave art was discovered in December, Toubon said the news was kept secret until yesterday "in order to insure the legal and physical protection of the site." Because of the delicacy of the paintings, the caves will not be open to the public.

CAPTION: A bear stands over a panther in one of the 300 ice age cave paintings discovered near Avignon. One French specialist said the find may be as important as the famous caves at Lascaux, because the animals in these paintings are often in action, a rarity in prehistoric art.

CAPTION: The art, including this painting of rhinoceroses in action, may be 20,000 years old, experts said.