Some fungi can cause disease in humans and other animals - The study of pathogenic fungi that infect animals is referred to as medical mycology. It is believed that humans started collecting mushrooms as food in prehistoric times. Mushrooms were first written about in the works of Euripides (480-406 B.C.). The Greek philosopher Theophrastos of Eresos (371-288 B.C.) was perhaps the first to try to systematically classify plants; mushrooms were considered to be plants missing certain organs. It was later Pliny the Elder (23–79 A.D.), who wrote about truffles in his encyclopedia "Naturalis historia". The word "mycology" comes from the Greek: μύκης ("mukēs"), meaning "fungus" and the suffix ("-logia"), meaning "study". The Middle Ages saw little advancement in the body of knowledge about fungi. However, the invention of the printing press allowed authors to dispel superstitions and misconceptions about the fungi that had been perpetuated by the classical authors. The start of the modern age of mycology begins with Pier Antonio Micheli's 1737 publication of "Nova plantarum genera". Published in Florence, this seminal work laid the foundations for the systematic classification of grasses, mosses and fungi. He originated the still current genus names "Polyporus" P. Micheli and "Tuber" P. Micheli, both dated 1729 (though the descriptions were later amended as invalid by modern rules). Note that when referring to the scientific name of a genus, the author abbreviation can optionally be added afterwards. The founding nomenclaturist Linnaeus included fungi in his "binomial" naming system of 1753, where each type of organism has a two-word name consisting of the "genus" and the "species" (whereas up to then organisms were often designated with Latin phrases containing many words). He originated the scientific names, still used today, of numerous well-known mushroom taxa, such as "Boletus" L. and "Agaricus" L.. At that period fungi were considered to belong to the plant kingdom, and so they find their place in his magnum opus "Species plantarum", but he was much more interested in higher plants and for instance he grouped together as genus "Agaricus" all gilled mushrooms which have a stem. There are many thousands of such gilled species, which later were divided into dozens of diverse genera and in its modern usage the genus "Agaricus" only refers to mushrooms closely related to the common shop mushroom, "Agaricus bisporus" (J.E. Lange) Imbach.