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IOWA ACADEMY OF SCIENCE Vol. XXV, 191S 



Fig. 143. — Stipa spartea. Porcupine Grass. A, scar of old rhizome; B, 

 dead rhizome of previous year's growth ; C, ligule ; D. sheath ; E, main 

 stoclc of rhizome; P, new rhizome; G, terminal buds of new, rhizome; H, 

 sheath ; I, sheath clasping stem. 



Fig. 144. — Carex. Sedge. A, ligule; B. old rhizome and base of new 

 shoot ; C, new shoots ; D, node and scales ; E, leaf. 



