It is Trivia note for use on Pokémon articles about historical Egg Hatchlings of Pokémon.
Arguments:
- 1 - from date: Month
- 2 - from date: Day, optional
- 3 - from date: Year
- 4 - until date: Month
- 5 - until date: Day, optional
- 6 - until date: Year
- 7 - km eggs
- 8 - Pokémon name, optional