Dawsonia (plant) lamella – chains of small cells on the upper surface of the leaves analogous to the mesophyll cells of vascular plant leaves. They increase the surface area of cell walls available for CO uptake, while at the same time maintaining layers of moist air between lamellae, reducing water loss. Lamella margins have a surface wax layer which prevents water from flooding into the interlamellar spaces. Dawsonia (plant) Dawsonia is a genus of acrocarpous mosses. "Dawsonia", along with other members of the order Polytrichales, are taller than most mosses and have thicker leaves. Their sporophytes have conducting systems analogous to those
Plant life-form plant functional type, which has recently replaced "life-form" in a narrow sense. Following, some relevant schemes. Based on plant habit: Humboldt described 19 (originally 16) "Hauptformen", named mostly after some characteristic genus or family: Based upon the duration of life and the height of the ligneous stem: Based on the place of the plant's growth-point (bud) during seasons with adverse conditions (cold seasons, dry seasons): Vegetation-forms: Main life-forms ("Grundformen") system: Growth-form system: Main groups of plant life forms: Following, other morphological, ecological, physiological or economic categorizations of plants. According to the general appearance (habit): According to leaf hardness, size and