Translation:Mishnah/Seder Moed/Tractate Chagigah/Chapter 1/6

One who did not offer the hagigah offering on the first Yom Tov of the festival may offer the hagigah throughout the festival or on the last Yom Tov of the festival. If the festival passed and one did not offer the hagigah--there is no longer an obligation to offer it. Concerning this it is said: A tiwsted thing cannot be made straight, and what is not there cannot be numbered.