Felix De Azara, a Spanish naturalist, born in Aragon, May 18, 1746, died there in 1811. He became a brigadier general in the Spanish army, and was wounded in the warfare against the Algerine pirates (1775). In 1781 he went to' South America as one of the commissioners for the settlement of the boundary between the Spanish and Portuguese possessions, and the researches which he prosecuted till 1801, despite the vexatious proceedings of the local Spanish officials, gave him distinction as an authority on the natural and political history of Paraguay and the Plata region. His Essai sur l'histoire naturelle des qiiadrupedes de la province du Paraguay was first published in French (Paris, 1801), and afterward in Spanish (Madrid, 1802) under the auspices of his brother, the chevalier Jose Nicolas de Azara (born in 1731, died in Paris in 1804), Spanish ambassador to France, favorably known by a Spanish translation of Middleton's Cicero and by other literary achievements. Felix de Aza-ra's masterpiece, Voyage dans l'Amerique me-ridionale depuis 1781 jusqu'en 1801 (4 vols., Paris, 1809), containing a narrative of the discovery and conquest of Paraguay and the Plata river, and in the last two volumes ornithological descriptions translated by Sonnini, was edited by the French naturalist Walckenaer, whose commentaries as well as those of Sonnini and Cuvier impart additional value to the work.

A Spanish translation by Varela has been published at Montevideo.