Silvery lutung or langur, Trachypithecus cristatus, and grivet monkey, Chlorocebus aethiops. Handcoloured copperplate stipple engraving from Frederic Cuvier's "Dictionary of Natural Science: Mammals," Paris, France, 1816. Illustration by J. G. Pretre, engraved by Miss Massard, directed by Pierre Jean-Francois Turpin, and published by F.G. Levrault. Jean Gabriel Pretre (1780~1845) was painter of natural history at Empress Josephine's zoo and later became artist to the Museum of Natural History. Turpin (1775-1840) is considered one of the greatest French botanical illustrators of the 19th century.