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IOWA ACADEMY OF SCIENCE Vol. XXV, 191S 



Hordeum jubaUim. Squirrel Tail. Figure 131. 



Slender, erect -wdnter annual. This species does not have a 

 creeping rootstock, but a short, somewhat thickened rhizome, 

 shoots producing- a tufted grass. An abundance of long fibrous 

 roots are produced. Leaves smooth, rolled in 'bud; blade flat, 

 long, linear, pointed, pubescent. Sheath compressed, pubescent. 

 Ligule acute, toothed. Collar wanting. 



Fig. 132. — Muhlenhergia Mexicana. Mexican Drop Seed. A, ligule; B, 

 sheath ; C, old culm ; D, old rhizome ; E, new rhizome with terminal shoot ; 

 F, buds from new rhizome. 



Muhlenhergia Mexicana. Mexican Drop Seed. Figures 132 

 and 133. 



A decumbent, slender, glabrous perennial. Resting period 

 from October until March. Rhizome, rather slender, creeping, 

 m'any new rhizomes branching from the nodes. New culms do 

 not always appear the following year at the base of the previous 

 year's growth. First new shoot appears at terminal bud or end 

 of rhizome, followed by several more from the same base. Rhi- 

 zomes very soaly, nodes one-half to one and one-half cm apart. 

 Roots very delicate, fibrous. Leaves, rolled in bud. Blades one- 

 third to one-half cm. wide, thin, flat, pale green. Sheaths com- 



