Ignus fatuus

Ignus fatuus is a Jack-o-Lantern.  The inhabitants of the Isles were keen on carving up gourds and poking light holes in the outer skin as kind of scary things to put out in the moors.  Seems like a waste of candles and food but nowadays it is replaced by the one on the front porch to let the trick for a treaters know someone is home with candy.

 No one is very sure how far back the idea of carving pumpkins goes but the jack-o-lantern - you remember?  Jack be nimble, Jack be quick, Jack jumps over the candle stick? -  certainly has some American roots - there is a poem called "The Pumpkin" by Whittier in 1850:

Oh!—fruit loved of boyhood!—the old days recalling,

When wood-grapes were purpling and brown nuts were falling!
When wild, ugly faces we carved in its skin,
Glaring out through the dark with a candle within!

All of which (witch) is more than you want to know.  Have a happy Halloween.  Keep the cats indoors.