CHARLES NICOLAS SIGISBERT, a French naturalist, was born of a good family, at Lunéville, on the 1st of February 1751. After having completed his education at the Jesuit University of Pont-à-Mousson, he became acquainted with Buffon and Nollet, who encouraged his taste for natural history. He obtained a commission in the marine engineer service, and was sent to Cayenne, where he distinguished himself so much by his energy and perseverance that he was made lieutenant on his return to France. He again visited Cayenne in 1775; but finding his health give way, he was induced to pass a winter as the assistant of Buffon. He subsequently joined the African expedition of Baron de Tott in 1777, and visited Egypt, Asia Minor, and Greece, before his return to France in 1780. He busied himself in agricultural affairs, and was appointed one of the administrators of the department of Meurthe. He contributed the volumes of fishes and cetacea to Buffon's Natural History, wrote part of the volumes on reptiles, edited a dictionary of natural history, and published several volumes of Voyages in Egypt and in Greece. Sonnini set out for Moldavia in 1810, but died on his return to Paris, from the effects of a fever which he had caught during his travels in the East. He deserves much credit for his labours as a naturalist; while in the department of archaeology and topography his researches were not distinguished by any degree of originality. A complete list of the works of Sonnini will be found in the Biographie Universelle.