THE TISSUES OF PLANTS, 19 
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Fia. 11. Fig. 12. 
Fie. 11.—Milk-tubes from a Spurge (Euphorbia). A, moderately magnified; B 
more highly magnined. and showing the bone-shaped starch-grains. 
Fig. 12.—Milk-vessels of a Heck aie (Scorzonera). A, a transverse section of 
the root; B, the same more highly magnified. 
walls (Fig. 11, B); in other plants they are thin-walled 
and are sometimes inclined to anastomose, From their 
