| [Vor. 11 
104 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
themselves by scaly bulblets which appear on the underground 
stems toward the end of the growing season. М. Eastwoodiae 
and M. primuloides produce runners above ground. А few 
species found in Mexico and in Australia are characteristically 
repent. 
The annual species are rarely more than three to six decimeters 
high as in M. brevipes and M. Bolanderi. The section ( пов is 
peculiar in that many of the species are nearly stemless, the 
flowers being produced in the axils of crowded basal leaves. 
Leaves.—As is the case in most polymorphic genera, Mimulus 
shows great differences in shape, texture, and size of the leaves. 
Throughout this genus simple leaves with little or no lobing are 
common. М. laciniatus is the only species with typically lobed 
or parted leaves, yet in a few of the other members of the section 
Simiolus there are small lobes at the base of the leaf-blade. The 
shape of the leaves within a single species in this section may 
vary to such an extent that descriptions of several species and а 
number of varieties have been wrongly based on leaf characters 
alone. Occasionally the leaves are mainly basal, this condition 
being found in M. primuloides and in some of the polymorphic 
species belonging to the section Simiolus as well as to (пое. 
The venation varies from typically feather-veined to a condition 
where several main veins arise from the base of the blade. The 
latter condition, being less common and found mostly in the 
more highly specialized groups, is regarded as of later derivation. 
Pubescence.—There is great diversity in the kind of hairiness 
within the genus, viscid- or glandular-pubescence being the. 
common type. Members of the section Eumimulus and many of 
the South American Simioli are typically glabrous. The single 
species in T'ropanthus is glabrous but the surface is covered with 
sessile glands. Diplacus is the only group in which branched 
hairs have been commonly found. A few species in the section 
Paradanthus have hairs which secrete a slimy sticky substance, 
this latter seeming to be a late development. Most of the 
annuals in Paradanthus, Eunanus, and Œnoe are glandular ot 
viscid-pubescent, and as they usually are found in dry and semi | 2% 
arid places the amount of hairiness may be due to the effect of 
their environment. | 
