The correct order is
(1) Pulvinus leaf base, Kranz anatomy, Tricarpellary gynoecium, Septicidal capsule.
(2) Foliaceous stipules, Scutellum, Tetracarpellary gynoecium, Septifragal capsule.
(3) Piston mechanism, Eustele, Monocarpellary gynoecium, Swollen placenta.
(4) Monodelphous stamens, Still roofs, Bicarpellary gynoecium, Unilocular ovary.