Possible Clues:

• Keep an eye on the twit in the back room
• The room up there is just about a little lousy for the prefect
• Lizard's egg eaten by African
• Prefect; a loudspeaker
• Keep track of
• A television or computer screen
• Checking device - VDU - lizard
• Check on - large lizard
• Keep an eye on new technology in an uncultivated environment
• Screen site