Ichthyosis, formerly known as 'pseudo-leprosy' is a rare genetic skin disease. It is inherited and not contagious, and causes dry, scaly skin giving the appearance of fish scales, amongst other problems. 'Ile des Papous' (Island of the Papuans) is probably the Doberai Peninsula, on the Indonesian part of the island of New Guinea. Illustration from 'Voyage autour du monde: entrepris par ordre du Roi...execute sur les corvettes de S M l'Uranie et la Physicienne pendant les annees 1817, 1818, 1819 et 1820 / par Louis de Freycinet'. This work, by Louis Claude Desaulses de Freycinet (1779-1842), was an account of a French voyage round the world between 1817 and 1820, and was published in Paris between 1824 and 1844.
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