 "Barting Over" was billed by FOX as the series 300th episode  because it was considered to be the 300th episode produced. However,  FOX does not count the Christmas Special pilot towards that total.  So technically, it was actually the 301st. FOX was very adamant  about airing the "300th" episode on the same day as the Daytona 500  auto race, which is one of the biggest ratings draws of the year for  the network, so they pushed the air date back to February 16th. So  when the episode finally did air, it was actually the 302nd to do so  (Christmas special included), even though FOX was hyping it up as  #300. To further add to the confusion, all previous milestone  episodes (100th, 138th, 200th, 250th) were based on airing order  rather than production order, and with the Christmas special  included.