IDENTIFICATION OF GRASSES. 27 



the presence or absence of claws, the pubescence and the general 

 shape of the blades, especially at the tips. The ligules of all are 

 very similar, the principal differences being in shape and length. 



ANALYTICAL KEY TO SMALL-GRAIN SEEDLINGS. 



A. Collar without clawlike appendages. 



49. Oats (Avena sativa). 



AA. Collar with clawlike appendages which clasp the stem more or less. 

 B. Claws hairy. 



C. Sheaths and blades finely pubescent, soft, and velvety. 



50. Emmer (Triticum dicoccum). 

 CC. Sheaths and blades not pubescent. 



D. Collar and claws large. 



51. Spelt (Triticum spelta). 

 DD. Collar and claws slender. 



52. Wheat (Triticum aestivum). 

 BB. Claws not hairy. 



C. Collar and claws large and prominent. 



D. Nerves of blades not prominent, upper surface rough. 



53. Barley (Hordeum sativum). 



DD. Nerves of blades broad and prominent, smooth on upper sur- 

 face. 



54. Polish wheat (Triticum polonicum). 

 CC. Collar and claws slender. 



D. Blades and sheaths sparsely hairy. 



55. Rye (Secale cereale). 



iDD. Blades and sheaths free from hairs. 

 56. Durum wheat (Triticum durum). 



DETAILED DESCRIPTIONS OF EIGHT SMALL-GRAIN SEEDLINGS. 



49. Oats (Avena sativa; fig. 53). 



Collar broad, separated into two parts by midnerve, free from claws, 

 finely hairy; ligule membranous, long, acute, toothed; sheaths sparsely 

 hairy ; blades hairy along margins, flat, rough, one-half inch wide. 



The blades are longer and more taperingly pointed than those of wheat. Some varieties 

 of spring oats are free from hairs on sheaths and blades. Spring oats have a more upright 

 habit of growth than the winter varieties. 



50. Emmer (Triticum dicoccum; fig. 54). 



Collar medium broad, with claws ; collar and claws sparsely hairy ; ligule 

 thin, membranous, acute, toothed ; sheaths finely pubescent, soft and vel- 

 vety, the hairs seen only with a lens, one-fourth inch wide, sharp pointed ; 

 blades prominently nerved. 





51. Spelt (Triticum spelta; fig. 55). 



Collar broad, similar to that of barley, with large, hairy claws; ligule 

 membranous, medium long, toothed, acute ; sheaths free from hairs ; blades 

 free from hairs near base except a few at margins, one-fourth inch or more 

 wide, sharp pointed on older, abrupt on younger plants ; nerves small. 



