Sponsored by The Society of French Explorers, The National Museum of Natural History, The Museum of Man and the French Government, twelve French scientists from the Ogowe-Congo Mission set out, along with photographers, on a fourteen-month expedition into Equatorial Africa to make a record of primitive tribes. Riding in giant log canoes known as pirogues, the team plans to travel the entire 600-mile length of the Ogowe River from its headwaters in the Congo to the coast. Deep in the jungle live the Babingans, a nomadic pygmy tribe. Their huts are made out of saplings and leaves called elephant ears. The scientists observe that, like other pygmies, the Babingans are less than five feet tall and often live to be very old. They use nets, made from the bark of the Kosa tree, to hunt game. After the animals are trapped, the Babingans kill them with spears and poison-tipped arrows. During an antelope hunt, a giant leopard, attracted by the kill, attacks a pygmy and is speared to death by the hunters. Every part of the antelope is used or is traded for other goods. Later, the pygmies celebrate with a dance. Their songs keep the Babinga history alive. Farther along the river, the expedition witnesses a Bateke wedding and ceremonial dance. The village of B'mamtu is located in country infested by the tsetse fly, which carries sleeping sickness. This disease is fatal to men and to their cattle. In the interior, the pirogue paddlers obtain permission from the local chief to hunt an elephant. Every part of the elephant will be used, including the ears, which are used to make drum heads. After the elephant is killed by men using ancient muskets, a ceremonial dance is held to kill the elephant's spirit. As the river runs along more open land, flamingos and hippopotamus are seen. Over 600,000 flamingos inhabit one stretch of the river. The expedition visits the Ubangi, who insert wooden disks into their lips to extend them, and the Pahouins, who live on the land between the river and the mountains. Continuing over some rapids, the expedition presses deeper into the Congo. The scientists see impala, a cousin of the antelope, who can jump as high as ten feet vertically and 40 feet horizontally. After a native crew member is killed by a lion during an overland expedition, the Masai king dispatches his warriors, armed with throwing spears, to kill the animal and avenge the death. The pirogues are then re-waterproofed, and the expedition continues inland to a part of the country that suffers from disease and insects. A fertility dance, during which the M'Ebits pray to their gods for the tribe's welfare, good crops, children and vigorous cattle, is witnessed. Another tribe, the Okandes, live near gorillas. For two nights and two days, during the season when the gorillas are at their wildest, a gorilla dance is held. Only the hunters take part in the dance, which is followed by a gorilla hunt. A 775-pound gorilla is killed as a sacrifice to the fertility god.