In his commentary on Demosthenes 19, D. M. MacDowell writes on section 314:
θοἰμάτιον καθεὶς ἄχρι τῶν σφυρῶν: letting the cloak slip down at the back in affected nonchalance. Cf. Cicero, Pro Cluentio 111 'illam usque ad talos dismissam purpuram'. Readers familiar with universities in which gowns are regularly worn will recognize the picture.