Egg-Mother's Tithe: Science Fiction

"Your tithe is due, and past due, egg-mother!" the collector chittered warningly. The mother fanned her wings in distress, as if a too-hot breeze had blown through her nest, and backed away. "Time," she managed to say. "Just a little time is all I need. Do not take one. These are special. Next clutch--next clutch you shall have your pick." "They're always special, egg-mother," the collector said, not without sympathy. The collector too had laid her clutches and guarded them carefully, though that time was many cycles in the past, and her egg-laying sac had dried up. It clung withered to her abdomen, though she had tattooed a delicate pattern upon it to indicate that she had born--

Inspiration: Due dates on things.
Story Potential: Medium.
Notes: A nice mind-stretch for me, but nothing too new here--just different from the usual well-trodden paths my ideas wind their way down.