SECRETORY CELLS OF LILY PISTILS. I. FINE STRUCTURE AND FUNCTION

The fine structure of the cells which line the canal of Lilium longiflorum pistils confirms the secretory function which has been ascribed to them. The cells differ in structure from the secretory cells which cover the stigma surface and are therefore referred to as canal cells rather than stigmatoid cells. Their most striking feature is an elaborate wall, 8–14 μ in maximum depth, on the side facing the canal, which with associated structures, we term the secretion zone. Pollination, which triggers chemotropic activity in the style and secretory activity in the canal cells, is not correlated with marked changes in the fine structure of the canal cells. The canal cells appear to fit well into that category which Gunning and Pate have termed “transfer cells.”