256
H. WALTER AND E. STADELMANN
Fig. 23. Encelia farinosa, semishrub, from the Tumamoc Hill near Tucson, Arizona
(from Walter, 1931, p. 135, Fig. 56; photograph by E. Walter).
Fig. 24. Hygromorphic, mesomorphic, and xeromorphic leaves from Encelia
farinosa. The twigs in the center of the photograph bear leaf primordia densely
covered with white hairs (from Walter, 1931, p. 135, Fig. 57; photograph by
E. Walter).