14 Raymond John Pool 
is 8 tog » thick. The lower cuticle is thick also (5 »), and it is 
thrown up into about as many papillae as there are epidermal 
cells. The chlorenchyma is very compact, being composed of two 
definite rows of closely aggregated palisade cells, with about four 
irregular rows of globose or spongoid cells packed closely to- 
gether in the lower portion of the leaf. There is no storage tissue, 
and, indeed, it is unnecessary that there should be with such per- 
fect cuticularization. The whole leaf is very smooth and firm, and 
the marginal indentations are tipped with strong spines. Nuclei 
are conspicuous in the cells of the epidermis. 
Lupinus pusillus. Plate II, fig. 12. 
The epidermis is composed of very large lens-shaped cells from 
which arise few epidermal hairs. The chlorenchyma is composed 
of four irregular rows of palisade cells, two rows on either side 
of a broad band of spongoid storage tissue, some cells of which 
contain chloroplasts. The older storage cells lack the chloroplasts. 
The whole leaf tissue is very close. The guard cells of the 
stomata are very small and well protected by the shadowing of 
the large adjacent cells of the epidermis. The holard was 10.8 
per cent in this situation. 7 
Lappula occidentalis. Plate II, fig. 13. 
This is one of the most common herbaceous associates of the 
Artemisia in the Fort Garland region. The leaf has a thick up- 
per and lower cuticle with many epidermal hairs. The chloren- 
chyma is composed of four rows of palisade, two rows on either 
side of a broad median band of milky or mucilaginous tissue 
whose cells are globose in transverse section. The vascular bun- 
dles are embedded in this tissue. No microchemical tests were 
made of the cell contents of this storage tissue. 
Drymocallis fissa. Plate II, fig. 14. 
This species is perhaps another invading form, but its leaf is 
a rather typical xerophyll. The epidermis is protected in a slight 
degree by the stiff epidermal hairs which arise from the large 
globose cells much like those of Lupinus above. The cells of the 
lower epidermis here, however, are only about one-half the size 
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