[f. L. ex- (see EX- pref.1) + int-us within + -INE1.] ‘The membrane of the pollen grain which lies between the Extine and the Intine’ (Syd. Soc. Lex., 1884).

1

1852.  in Brande (Supplement).

2

1866.  in Treas. Bot.

3