Many of these films are available for rental from the distributors. About Sharks National Geographic, 1981.
Sharks prowl the ocean depths and swim near sunny, sandy beaches.
Students will be introduced to sharks and learn that only a few of them are dangerous to man. Most of the approximately 300 species of sharks feed on fish and other sea creatures. Length 12 min. Adaptation in Mollusks American Institute of Biological Sciences, 1967. This film considers modifications that have produced today's great variety of the ancient phylum of a hypothetical primitive mollusk, and shows special adaptations in sea and land snails, the carnivorous turban snail, sea slugs, clams and oysters.