CHAPTER XXI 
SOME SPECIAL ADAPTATIONS 
581. The plant body (sporophyte) of the Anthophyta, 
while standardized as to general plan, is very plastic as 
to the details of its structure. This plasticity has enabled 
it to respond so fully to various needs as to bring about 
marked changes in its size, form, proportions of parts, 
surface characters, etc. Only the more important of 
these need be noticed here. 
582. For particular purposes some parts of the plant 
body may have a special development, as the thorny (not 
et, OO 
Fic. 195.—Standard Fria. 196.—Runners, above Fie. 197. Oe ap: bulb, 
plant (Anthophyta). and under ground. and root. 
parenchymatous) leaves of the Barberry, the thorny 
leafless branches of the Honey Locust (both protective), 
the runners of the Strawberry above ground, and the 
under-ground rootstocks of the Canada Thistle (both for 
vegetative reproduction). 
583. Many plants store up food substances in some 
part of the plant body, resulting in considerable changes 
in form. Thus the lower part of the stem may be 
spherically enlarged, as in the so-called corms of Arisaema 
and Gladiolus. In the bulbs of many plants, as the 
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