I need to do a project about butterworts and I can't find an answer to this question!
I could not find any direct information about this, but if I had to guess, I would say that it is a specialized case or container, like an Edwardian case or a terrarium, meant to house butterworts.
These articles should help:
http://mnfi.anr.msu.edu/abstracts/botany/Pinguicula_vulgaris.pdf
https://www.gardeningknowhow.com/houseplants/butterwort/how-to-grow-butterworts.htm
n the leaves, they simply fly away! I have a gnat problem at home and initially the plants was able to trap over 100 gnats but ver y few lately. n the leaves, they simply fly away! I have a gnat problem at home and initially the plants was able to trap over 100 gnats but ver y few lately.
It may not be getting the proper light, water, and temperature. This article will help get it back in shape:
https://www.gardeningknowhow.com/houseplants/butterwort/how-to-grow-butterworts.htm