Nieremberg saw an unpublished manuscript of Hernandez. Many of his descriptions of plants and animals relied upon Hernandez and other sources from Mexico and Peru. In classification, Nieremberg retained Hernandez’ use of native Nahuatl names. Some of his woodblocks are the first known illustrations of their species, including the manatee and opossum (shown with young in a pouch). He mentioned the hunting of bison (Vaccas Sibolenses) by the Apache. Animal species mentioned include the jaguar, raccoon, three-toed sloth, porcupine, beaver, armadillo, rattlesnake, iguana, emu, bird of paradise, emerald toucan, and crocodile. Plant species include tobacco, guiacum, and the passion flower. He recommended the medicinal use of tobacco and the tail of the armadillo for ear disorders.