'PERHAPS the greatest surprise of the exhibition is the Glasgow Annunciation . . . That so important a picture should not have been even mentioned in Horne's monumental work is extraordinary in view of the immense pains he took to make an exhaustive study of all the available material. There is no one now living who can speak with anything like his authority to the authenticity of a Botticelli, there is no one who knew so minutely as he did what are the alternatives in the matter of immediate followers and imitators of the master.