RHIZOME.—CREEPING STEM. 119 
from itsupper. These stems sometimes creep for along distance 
in this way, and have their upper surface then marked by scars 
(fig. 234, c, c), which are caused by the falling off of former 
leaves, or of aerial herbaceous branches or flower-stalks, by which 
character they may be commonly distinguished, even when in a 
dried state, from true roots. Such stems are found in the Iris, 
Sweet-flag, Ginger, Turmeric, Solomon's Seal, Fern, and many 
other plants. In some cases these rhizomes are placed in a 
vertical direction in the earth (erect rhizomes), and they then 
bear a great resemblance to roots, as in the Devil’s-bit Scabious 
(Scabiosa succisa), where such a rhizome is commonly known as 
a premorse root (fig. 272). The rhizome being generally, as we 
have seen, partly beneath the surface of the ground, forms there- 
fore a natural transition to the description of subterranean stems. 
Fic. 233. 
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Fig. 233. A portion of the rhizome of a species of J7is.——Fig. 234. A por- 
tion of the rhizome of the Solomon’s Seal (Polygonatum multifiorum). 6. 
Remains of the flowering stem of the present year. 0b’, Terminal bud. 
c, c. Sears produced by the decay of the flowering stems of the two pre- 
ceding years. 7, 7. Rootlets. 
2. Subterranean Modifications of the Stem and Branches.—A\ 
these modifications of the stem and branches were formerly con- 
founded with roots, and they are still thus designated in common 
language. They are distinguished, however, from roots, either 
by the presence of buds, or by scales (cataphyllary leaves), or by 
the presence of scars on their surface which are produced by the 
falling off of former leaves or buds. The different kinds of aerial 
stems described above, when partially subterranean, may be also 
distinguished in a similar manner from roots. 
a. The Creeping Stem (fig. 235).—This kind of stem is called 
in common language a creeping root. It is a slender branch 
which runs along beneath the surface of the earth, emitting small 
roots from its lower side, and buds from its upper, in the same 
manner as the rhizome, and it is considered by many botanists 
as a variety of that stem. The only differences existing between 
the creeping stem as defined above and the rhizome, are its 
