I don't think we have anything from the Bard in all this long list do we?
I can't find anything specifically Megalithic, but there's this- one of the sonnets, about non-reporting detectorists.

Of what coarse metal ye are moulded.

Degenerate and base art thou,
An infinite and endless liar, an hourly promise breaker,
The owner of no one good quality.

You speak an infinite deal of nothing
Whilst swallowing the treasure of the realm

Pall thee in the dunnest smoke of Hell!
Thou art baser than a cutpurse.
Out of my sight! Thou dost infect my eyes.