Am.  jour.  Pharm. ) 
April,  1877.  / 
Xanthium  Spinosum. 
159 
in  this  country,  and  since  the  plant  has  been  naturalized  in  various  parts 
of  the  United  States,  we  present,  with  the  present  number,  a  plate 
which  has  been  copied  from  the  "  Swiss  Pharmaceutical  Weekly," 
and  represents  a  branch  of  the  plant  in  natural  size. 
The  genus  Xanthium  belongs  to  the  natural  order  of  Compositae, 
tribe  Senecionideae,  sub-tribe  Melampodineae,  division  Ambrosieas  of 
DeCandolle.  It  is  characterized  by  having  the  staminate  and  pistillate 
flowers  in  different  heads  upon  the  same  plant  ;  the  involucre  of  the 
former,  which  are  placed  at  the  top  of  the  branches,  is  sub-globose, 
consists  of  free  scales  placed  in  one  row,  and  contains  many  florets 
with  clavate,  shortly  five-lobed  corollas.  The  pistillate  heads  have  an 
oblong  or  ovoid  involucre,  which  is  closed,  coriaceous,  armed  with 
hooked  prickles  and  one  or  two  strong  beaks  at  the  apex,  and  contains 
two  florets  with  filiform  corollas,  no  stamens  and  flat  akenes  des- 
titute of  pappus.  The  plants  of  this  genus  are  all  coarse-looking, 
annual  weeds,  with  stout  branching  stems;  and  alternate  leaves,  and  are 
known  by  the  trivial  names  of  clot-weed  and  cocklebur. 
The  species  under  consideration  is  originally  indigenous  to  the 
southern  part  of  Europe,  from  Southern  Russia  west  to  France,  but 
has  gradually  spread  farther  north  into  Hungary,  Bohemia,  Silesia, 
Switzerland  and  Alsace,  but  in  most  places  it  occurs  but  sparingly,  the 
farmers  aiming  at  its  extirpation  on  account  of  its  rapidly  spreading 
into  the  fields  to  the  great  injury  of  the  crops.  It  has  likewise  been  to 
some  extent  introduced  into  most  civilized  countries,  and  in  the  United 
States  is  found  spontaneous  and  completely  naturalized  in  the  eastern 
section  from  the  New  England  States  south  to  Georgia,  growing  in 
waste  places  and  neglected  fields,  near  the  sea  board  and  along  rivers. 
Dr.  W.  Darlington,  in  his  "  Flora  Cestrica,"  1 853,  strongly  advocates 
its  total  extirpation,  and  states  that  u  some  years  since  the  authorities 
of  one  of  our  cities,  where  it  was  becoming  a  great  nuisance  in  the 
streets,  enacted  an  ordinance  against  it,  denouncing  it  by  the  name  of 
Canada  thistle  /" 
It  produces  a  terete  striate  and  pubescent  stem,  from  one  to  three 
feet  in  height,  and  has  lanceolate  or  ovate-lanceolate,  shortly  petiolate 
leaves,  which  are  white  downy  beneath,  the  lower  being  three-lobed, 
the  upper  more  or  less  cut-toothed  or  entire.  At  the  base  of  each 
leaf  are  stipules,  consisting  of  sharp,  three-forked,  yellowish  spines, 
frequently  attaining  an  inch  in  length  ;  the  fertile  burs  are  crowned 
