ALLEGRI, GREGORIO (1582-1652), Italian priest and composer, was born at Rome and studied music under G. Maria Nanini, the friend of Palestrina. He was a member of the Sistine chapel choir from 1629 until his death on Feb. 18, 1652. His most famous composition is the Miserere, performed once a year in Holy Week at the Sistine chapel, the score of which was jealously guarded for a century. But in 1769 Mozart, then a boy of 13, heard it and wrote it down *from memory—a wonderful feat— and Dr. Burney afterwards (17 71) obtained a copy and published it. Two volumes of concertos (published 1618-1 g ), and two vol umes of motets (published 1620-21) are available, but much of his work remains in manuscript.