E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Dissolute young scape, graces, whose delight was to worry the watchmen, upset sedans, wrench knockers off doors, and be rude to pretty women, at the close of the seventeenth century. The name comes from the first line of Virgils first Eclogue, Tityre tu patul recubans sub tegmine fagi (Tityre Tus loved to lurk in the dark night looking for mischief). Tus = tuze.