R.A.S. Seaford in OCD(4) s.v.; and see also theta 283.
[1] Ikarion (also called Ikaria) was one of the demes of Attica whose pre-classical history and stature led it often -- after as well as before Kleisthenes -- to be termed a "city", polis. For Ikarion as the place where both tragedy and comedy were said to have originated see e.g. Athenaeus, Deipnosophists 2.40A-B [2.11 Kaibel]; and generally D. Whitehead, The Demes of Attica (Princeton 1986) index s.v.
[2] R.A.S. Seaford in OCD(4) s.v. Epigenes(1). (epsilon 2262 is a later Athenian homonym.)
[3] According to Pickard-Cambridge [below] 76 the meaning here is that Thespis hung the strung flowers of the herb purslane over his face as a disguise.
[4] "But what the words 'in linen alone' mean is uncertain; they may mean 'of linen only, not of cork or wood', or 'of linen without paint or colouring', or 'of linen without any stiffening'." Pickard-Cambridge [below] 79.
[5] 536/5-533/2.
[6] See Heraclides 150 Schutrumpf for discussion of the possibility that these plays were forged by Heraclides of Pontus.