ATTHIS (an adjective meaning "Attic"), the name given to a monograph or special treatise on the religious and political his tory, antiquities and topography of Attica and Athens. During the 4th and 3rd centuries B.C., a class of writers arose, who, mak ing these subjects their particular study, were called atthidographi, or compilers of atthides. The first of these was Clidemus or Clito demus (about 378 B.c.) ; the last, Ister of Cyrene (d. 212 B.C.) ; the most important was Philochorus (first half of the 3rd century B.e. ), of whose work considerable fragments have been preserved.