century eggs and cobwebs
Cobwebby eggs are like 'pei-tan' (century eggs): They look like regular bird's eggs from afar, albeit coated with some dirt. They live up to their names, and remain eggs till their life span is over, or till cobwebs form from their being stationary for so long! These eggs serve no fruitful purpose except to resemble regular eggs, and maybe become a dish for somebody to consume!
But normal eggs hatch, the baby birds flap their wings, (and dirty the nest, and make Mama bird cry), then fly away to roost in their own family nests. May the teachers of the world never have cobwebby eggs in their nests!
