Fig. 9.

Oncidium heteranthum var. album: fertile flower, TEM. (A) Outer cell wall of glabrous epidermal cell of callus with associated osmiophilic cuticle. (B) Granular cytoplasm of epidermal cell with vesicles present in the periplasmic space (arrows) and a plastid lacking both starch and plastoglobuli. (C) Parietal cytoplasm with mitochondria and short profiles of rough endoplasmic reticulum. The vacuoles generally lack myelin-like figures. (D) Granular cytoplasm of sub-epidermal cell containing mitochondria and rough endoplasmic reticulum. (E) Sub-epidermal cell with plastids containing plastoglobuli and starch. (F) The inner tangential walls of epidermal cells, adjacent to those of the sub-epidermal tissue are relatively thick. The cytoplasm contains both plastids and mitochondria. Scale bars = 1 μm, 200 nm, 1 μm, 1 μm, 1 μm, 2 μm, respectively. CW, cell wall; Is, intercellular space; m, mitochondrion; P, plastid; RER, rough endoplasmic reticulum; st, starch; V, vacuole.