Calybium and cupule

The fruit cups or cupula (Latin for "little barrel, cup ") is a woody envelope with scales or spines that the fruits of the Fagaceae in whole or in part. These fruit cups can be found for example in beechnuts and acorns.

In this context, Curt grotto joke assigns the oak, the beech, sweet chestnut and hazel is not appropriate today's System Family of the cups Früchtler in Our Forest ( 1907).