Am"ja0nU!'iF9iarm"}       Vegetable  Drugs  Used  in  Mexico.  5 
ligules  in  one  row  and  pistillate,  the  tubular  florets  hermaphrodite ; 
akenes  cuneiform  ;  pappus  double,  the  inner  row  reddish,  and  the 
outer  row  short  and  whitish;  odor  mild,  taste  bitter.  Resin,  yellow 
color,  tannin,  gallic  acid,  gum,  fat,  bitter  principle,  and  a  trace  of 
volatile  oil  were  ascertained  to  be  present  by  Pr.  Reyes  Bruciaga; 
arnicine  is  absent.  The  flowers  are  known  as  arnica  del  pais,  and 
are  employed  in  the  place  of  arnica  flowers;  but  such  substitution 
should  not  be  made,  nor  has  it  been  proven  that  they  have  the  same 
properties. 
Laennecia  parvifolia,  DeCandolle ;  near  Toluca  and  in  the  north- 
eastern part  of  the  valley  of  Mexico.  Leaves  sessile,  oblong,  acute, 
featherveined,  tomentose ;  heads  ligulate ;  involucre  imbricate; 
pappus  silky  ;  inodorous,  bitter.  A  neutral  amorphous  yellow  bit- 
ter principle  was  obtained  by  Sandoval,  besides  resin,  tannin,  gum, 
etc.  The  plant,  which  is  known  as  simonillo  or  false  zacatichichi, 
has  been  used  by  Dr.  Altamirano  in  the  form  of  infusion  against 
biliary  calculi,  and  the  extract  in  pills  as  an  aperient. 
Parthenium  Hysterophorus,  Linne,  grows  in  the  valley  of  Mexico, 
Orizaba,  Cordoba,  Monterrey,  etc.,  and  is  known  as  cicutilla  confitilla 
or  yerba  amarga.  For  description  and  use  of  the  plant,  see  Amer. 
Jour.  Phar.,  1886,  p.  451  ;  1887,  p.  70,  and  1890,  p.  121. 
Piqueria  trinervia,  Cavanilles.  Herbaceous ;  stem  and  branches 
with  two  lines  of  hairs ;  leaves  opposite,  oval-lanceolate,  serrate, 
three-nerved ;  heads  homogamous  with  the  white  florets  perfect ; 
involucral  scales  four,  mucronate ;  receptacle  flat,  naked ;  akenes 
reversed  pyramidal,  pentagonal,  five-ribbed,  and  without  pappus. 
Frias  obtained  from  the  plant  volatile  and  fixed  oils,  amorphous 
acid,  etc.  The  plant  is  popularly  known  as  yerba  del  tabardillo  or 
de  San  Nicolas,  and  is  employed  in  infusion  as  a  stimulant  and 
febrifuge. 
Peritre  del  Caucaso,  different  species  of  Pyrethrum,  furnish  the 
well-known  insect  powder,  which  is  employed  for  killing  fleas  and 
other  parasites. 
Senecio  Grayanus,  Hemsley  (Cacalia  decomposita,  Asa  Gray),  and 
S.  cerviarisefolius,  Hemsley,  grow  in  Chihuahua,  the  second  species 
also  in  Oaxaca  and  Chiapas,  the  plants  being  known  as  matarique, 
maturin  or  guereua.  The  rhizomes  vary  in  form  and  attain  a  thick- 
ness of  about  3  cm.  ;  they  are  gray,  above  with  a  dingy  gray  tomen- 
tum,  and  with  irregular  depressions  and  thin  scales  upon  the  sur- 
