CHAPTER XXI 

 SO:\IE SPECIAL ADAPTATIONS 



681. 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 



Fig. 195. — Standard Fig. 190. — Runners, above 

 plant (Anthophyta). and under ground. 



Fig. 197 — Corm, bulb, 

 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 i)lant 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 iiuiiiy plants, as the 



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