During her research, Jane found that the 'flute a bec, which looked very like the recorder, was a precursor to the familiar 'transverse flute' only adopted later in Vivaldi's lifetime.
Because the flute a bec looks so like a recorder, the confusion is not surprising and there should perhaps have been an historical note in the book to explain how the flute developed during the course of the 18th Century.
The recorder was known under that name in England until the 1670s, when the new Baroque type was introduced from France under the French names "flute," "flute douce," or "
flute a bec," later changed to "common flute"; the transverse flute was called "flute" until the 1670s, then "German flute," "traversa," or some equivalent thereof.
4 (April 1971): 222-30; and Robin Troman in her unfinished series of articles on "Technique contemporaine de la
flute a bec,"
Flute a bec & instruments anciens 11 (June 1984): 12; 13/14 (December 1984/March 1985): 15; 15 (June 1985): 6-8; 16 (October 1985): 2; and 19 (September 1986): 3-4.