172 
Parthenium  Hysterophorous. 
Am.  Jour.  Pharm. 
April,  1897. 
stomata  and  beset  with  several-celled  tapering  hairs  [Fig.  6).^:.  The 
important  characteristics  of  the  powder  are  the  prickled  pollen 
Fig.  j.  Outer  disc  floret,  attached  to  chaff",  magnified  about  forty-eight 
diameters. 
grains,  the  hairs  and  longitudinally  striate  tissue  of  the  chaff,  the 
tapering  hairs  of  the  leaves,  the  reticulated  anther  walls  and  numer- 
ous spiral  cells  of  various  sizes  (Fig.  f). 
