14 



INTRODUCTION. 



With respect to its surface, it i 



Smooth, destitute of aJl kinds of hairiness. 



Even, destitute of all kinds of inequality. 



Polished or Shining, smooth and reflecting light. 



Viscid or Clammy, covered with a glutinous juice. 



Scaly, covered with scales. (Fig. 15.) 



Warty, covered with small hard protuberances. 



Papillous, covered with small soft protuberances. 



Rough or Uneven, covered with inequalities of any kind, as 

 opposed to even. 



Prickly, covered with prickles. 



Bristly, covered with stiff hairs. 



Shaggy, covered with very long, soft, generally white hairs. 



Woolly, covered with long, soft, interwoven, or tortuous hairs. 



Hairy, covered with long, soft, straight hairs. 



Downy, covered with soft, fine hairs. 



Hoary, covered with close, white hairs, extremely fine. 



Glaucous, covered with a pale greenish-blue mealiness, consist- 

 ing of minute particles of the nature of wax. 



Striated or Streaked marked with parallel longitudinal lines. 



Furrowed or Grooved, marked with larger alternately promi- 

 nent and depressed lines. When the lines become wider the stem 

 is Cornered or Angular. 



Solid, uniform throughout. 



Hollow, having a large internal cavity. 



Pithy, having the central part filled with pith. 



There is a kind of stem, peculiar to grasses and other allied 

 plants, which is named the Straw or Culm. It presents the fol- 

 lowing varieties : 



Jointed, with cylindrical hollow parts, united by a contracted 

 solid part. (Fig. 16.) 



Knotted, when the joints are enlarged. (Fig. 17.) 



Gcniculate or Kneed, when the joints are bent like a knee. 

 (Fig. 18.) 



It may be solid, round, triangular, smooth, rougli, hairy, or 

 downy. 



