Vegetative Anatomy ■ — Carlquist 
197 
taxonomic significance is necessarily implied 
by this arrangement. The groups below, how- 
ever, do appear to be natural groups in some 
instances. For each group, the illustrated spe- 
cies is used as a basis for description, and the 
species most closely resembling it are listed 
beneath, with the features by which they 
differ mentioned in parentheses. 
1. D. Kntidsemi (Fig. 1). Leaf bifacial; cells of 
upper epidermis larger than those of lower 
epidermis, thin walled; 1 layer of palisade 
present; bundle-sheath extensions present 
on major veins only; fibrous bundle cap 
present only on major veins; secretory 
canals 4 near larger veins, 1 or 2 near smal- 
ler veins; trichomes absent at maturity. 
Figs. 1-6. Leaves ot Dubautia. (1-5) Leaf transections. (1) D. Knudsenti, X 75. (2) D. railliardioides, X 67. 
(3) D. latifolia, X 95. (4) D. tvaialealae, X 87. (5) D. Menziesii, X 67. (6) D. lonchophylla, portion of cleared leaf 
to show marginal trichomes, below, and secretory canals, which appear as darker lines (on account of resins) 
beside two larger veins, X 58. 
