pen trough (pentrof)

The trough in which the penstock of a water-wheel is placed. Pentstemon (pent-ste'mon), n. [NL. (Mitchell, 1748), irreg. for * Pent a stem on or * Penteste mon, so called as having the fifth stamen, commonly absent in kindred plants, present as a conspicuous rudiment and in rare cases perfect; pent-stock (pent's tok), n. Same as punstock. Pentzia (pent'si-a), n. [NL. (Thunberg, 1794), after C. J. Pentz, a student under Thunberg.] A genus of composite plants of the tribe An the mideæ, characterized by the absence of chaff, by having the bracts in many rows, and five angled achenes crowned with a cleft and cuplike pappus. The 11 species are all South African. They are small shrubs, hoary with whitish glandular hairs, and bearing small alternate wedge-shaped toothed or di ected leaves, and yellow flowers in small heads, usually in corymbs. P. virgata is the sheep fodder bush of Africa, valuable in planting deserts because it roots extensively from decumbent branches, and covers ground rapidly.