Note 001
From Chapter 53 of the Decline & Fall

The epithet of Porphyrogenitus, born in the purple, is elegantly defined by Claudian:

Ardua privatos nescit fortuna Penates;
Et regnum cum luce dedit. Cognata potestas
Excepit Tyrio venerabile pignus in ostro.

And Ducange, in his Greek and Latin Glossaries, produces many passages expressive of the same idea.