to mollusc shells. In 1692 Martin Lister published Historia Conchyliorum, a comprehensive conchological text with more than 1,000 engraved plates. George Rumpf, or "Rumphius", (1627–1702) published the first genuine mollusc taxonomy. He suggested the categories "single shelled ones" (modern Polyplacophora, limpets, and abalone), "snails or whelks" (Gastropoda), and "two-shelled ones" (Bivalvia). He did not include the tusk shells or the internal shells of the cephalopods. Many of Rumpf's terms were later adopted by Carl Linnaeus. The study of zoology, including conchology, was revolutionized by Linnaeus and his system of binomial nomenclature. Six hundred eighty three of the approximately 4,000 animal species Linnaeus described are now considered to be molluscs, although Linnaeus placed them in several different phyla at the time. The English word "conchology" was coined in the 1770s by the British Sephardi naturalist Emanuel Mendes da Costa, who published The Elements of Conchology: or, an Introduction to the Knowledge of Shells in London in 1776. Since 1700 a number of prominent conchologists have published their studies of shells. John Mawe (1764–1829) produced arguably the first conchology guidebook, The Voyager's Companion or Shell-Collector's Pilot, as well as The Linnæan System of Conchology. Hugh Cuming (1791–1865) is famous for his huge collection and numerous discoveries of new species. Thomas Say wrote the fundamental work American Conchology, or Descriptions of the Shells of North America, Illustrated From Coloured Figures From Original Drawings, Executed from Nature in six volumes (1830–1834). R. Tucker Abbott was arguably the most prominent conchologist of the 20th century, authoring dozens of books and working as museum director of the Bailey-Matthews Shell Museum. His most best-known works are American Seashells, Seashells of the World, and The Kingdom of the Seashell. John DuPont is also known for his extensive collection which he donated to the Delaware Museum of Natural History in 1984. The Japanese emperor Hirohito also amassed a huge collection, and was a competent and respected amateur conchologist. In 1950, Joyce Allan, an Australian conchologist working as curator of shells at the Australian Museum, authored Australian Shells. This was the first book to catalogue the majority of Australian molluscs in detail and was highly regarded within the scientific community and mollusc collectors. Museums Many museums worldwide contain very large and scientifically important shell collections. However, in most cases these are research collections not as readily accessible to the general public as exhibits. the world's largest assemblage of mollusc shells