In botany terms the difference between involucel and phyllary
is that involucel is an involucre that forms at the base of a flower cluster within a compound inflorescence while phyllary is an individual bract within an involucre or involucel.
involucel
English
Noun
(
en noun)
(botany) An involucre that forms at the base of a flower cluster within a compound inflorescence.
phyllary
English
Noun
(phyllaries)
(botany) An individual bract within an involucre or involucel.