Alexander Dyce, A General Glossary to Shakespeare's Works

apparition “of an armed Head rises—An,” MACBETH, iv. 1. 68 ; “An apparition of a bloody Child rises,” MACBETH, iv. 1. 76 ; “An apparition of a Child crowned, with a tree in his hand, rises,” MACBETH, iv. 1. 86. “The armed head represents symbolically Macbeth's head cut off and brought to Malcolm by Macduff. The bloody child is Macduff untimely ripped from his mother's womb. The child with a crown on his head, and a bough in his hand, is the royal Malcolm, who ordered his soldiers to hew them down [each] a bough and bear it before them to Dunsinane” (UPTON, — whose explanation is at least very ingenious). I may add here a remark of the truly learned Lobeck: “Mortuorum capita fatidica jam multo ante Bafometum et illud galeatum phantasma, quod in fabula Shakspeariana introducitur, memorat Phlegon, Mirab. iii. 50, etc.” Aglaophamus, p. 236 (note).