Possible Clues:

• Hooked to sleep there at the pub
• Having projecting points, perhaps wire
• Rod on bottom, intended to sting
• Covered with protective spines or thorns
• Message from berth in pub, perhaps, something sharp
• Like cow pasture wire, often
• -- -wire fence
• (Of wire) having short spikes at intervals
• Like cruel joke uncovered about bishop
• Thorny — cutting