the nests of certain species of salangane (birds of the suborder Apodidae, which externally somewhat resemble swallows; hence the Russian name, lastochkiny gnezda, “swallows’ nests”). Edible birds’ nests are constructed entirely or almost entirely from secretions of the salivary glands. They are highly valued in some countries of Southeast Asia as a delicacy used in the preparation of soups and other dishes. The gathering of edible birds’ nests entails great difficulty, since salanganes attach them beneath the ceiling in the depths of high caves and grottoes.