National Geographic : 1941 Feb
Siaiiunai ueograpeue ucie Kodaacnrome by Lieutenant Dayton Seiler, U.S.N. With Beads of Polished and Matched Seashells, San Blas Indians Paddle Out toMeet the Trading Boat Skillfully the islanders handle their cayucas, or dugout canoes, made by hollowing and burning out the trunks of trees.Often the Indians fitaboat with sails and make the 75-mile open-water trip to Colon. The chief form of exchange is coconuts. Seven coconuts are equivalent toanickel, fourteen toadime.