Julius Arnold was a German anatomist and pathologist who described a case of what is now recognized as a Chiari I malformation. Hans Chiari: was an Austrian pathologist who, in 1891, first systematically described Chiari malformations, including types I, II, and III. He later described a fourth type in 1895. McRae's line is named after Lieutenant-Colonel John McCrae, a Canadian poet, physician, author, and soldier. He is best known for writing the poem "In Flanders Fields".