The unicellular glandular hairs are either sessile or stalked.
Sessile unicellular hairs occur in digitalis leaves.
Stalked unicellular hairs of digitalis are shown on Plate 60, Fig. 2.
Unicellular uniseriate stalked glandular hairs occur on the stems of the common house geranium (Plate 61, Fig. 2), on the leaves of butternut, the leaves and stems of marrubium peregrinum (Plate 98, Fig. 5), and in arnica flowers. The stalk varies from two to ten cells; in eriodictyon the cells vary from four to eight cells.
Unicellular multiseriate stalked glandular hairs are not of common occurrence.
MULTICELLULAR GLANDULAR HAIRS
Multicellular glandular hairs are divided into two groups: first, sessile; and secondly, stalked hairs.
Multicellular sessile glandular hairs occur on the leaves of peppermint (Plate 60, Fig. 3), horehound (Plate 97, Fig. 7), and in hops (Plate 60, Fig. 4). In each of these hairs there are eight secretion cells.
Stalked glandular hairs are divided into two groups: first, uniseriate stalked; and secondly, multiseriate stalked glandular hairs.
Multicellular uniseriate stalked glandular hairs occur on the leaves of tobacco (Plate 61, Fig. 4), belladonna (Plate 61, Fig. 1), and digitalis (Plate 60, Fig. 2), and of the fruit of rhus glabra.