Possible Clues:

• Innocent
• Innocent chicken — one left inside
• One student wearing yellow is innocent
• Like a coward clutching contents of till -- innocent?
• Free from blame
• Innocent Irish lad originally feeding chicken?
• Pure, like an unadorned lily, so to speak?
• Innocent conjecture gets around till squashed
• Innocent officer implicated in deceit on ship
• Innocent officer looking into treachery on ship