This is the season for demons’ lanterns! The above picture shows demon’s lanterns or hoozuki on sale. The botanical name is Phrysalis alkekengi Linn. var. franchetii. There is a market actually called Demon Lanterns Market at Asakusa Temple in Tokyo where they sell all the usual summer things like hoozuki, morning glories, wind chimes, etc.
At this site you can read all sorts of info about hoozuki crafts, ikebana, haiku, etc.
Demon’s Lanterns are not to be confused with the other kind of lantern flower — the Abutilon / Japanese (or some call it Chinese) lantern flower that’s in bloom now.