340    Materia  Medica  of  the  Mexican  Pharmacopoeia,  {^"'•j^iy^'iSs*'^™ 
nat.  ord.  Bombace^ie,  indigenous  to  Mexico.  The  flowers  are  used 
internally  in  epilepsy,  and  as  an  emollient  in  ophthalmia. 
ilrbol  del  Peril,  Schinus  Molle,  Lin.,  nat.  ord.  Terebinth acese, 
grows  in  various  parts  of  Mexico.  The  leaves,  masticated,  serve  as  a 
remedy  for  loose  teeth  and  atonic  ulcers  of  the  mouth.  The  fruit, 
known  as  Pimienta  de  America,  is  stomachic,  stimulant  and  diuretic; 
it  contains  a  notable  quantity  of  sugar  and  may  be  used  for  the  pro- 
duction of  alcohol  and  vinegar.  The  bark  has  astringent  and  bal- 
sauiic  properties.  The  gum-resin  was  examined  by  Manuel  C.  Jim- 
enex,  of  Mexico;  it  forms  milk-white  tears,  varying  in  size  and 
becoming  gradually  reddish  yellow,  softens  on  mastication,  has  a  bitter 
and  sharp  taste  with  an  aftertaste  resembling  that  of  cubeb,  and  a 
disagreeable  odor,  becomes  soft  at  35°  and  melts  at  40°  giving  off 
white  fumes  and  an  odor  like  frankincense.  Its  powder  is  dingy 
white  and  is  easily  emulsionized  with  water.  It  is  composed  of  40 
gum,  60  resin  and  a  small  quantity  of  volatile  oil.  Two  or  three 
drops  of  the  concentrated  emulsion  are  used  for  the  removal  of  spots 
on  the  cornea. 
Aristoloquia  larga  and  A.  redonda,  the  rhizomes  of  the  European 
Aristolochia  longa  and  A.  rotunda,  Lin.,  are  rarely  employed  as  tonics 
and  stimulants. 
Arnica  montana,  Lin.  The  root,  leaves  and  flowers  are  employed  ; 
however,  Heterotheca  inuloides,  Cassini,  is  frequently  substituted  for 
the  former.  The  ray  florets  are  pistillate,  the  receptacle  flat  and  alve- 
olate, the  involucral  scales  imbricate  and  linear,  the  akenes  of  the  ray 
oblong  and  smooth,  those  of  the  disk  cuneiform  and  downy,  the  lower 
leaves  petiolate  oval  and  dentate,  and  the  upper  ones  sessile,  lanceolate 
and  entire.  The  chemical  constituents  and  the  therapeutic  action  of 
this  plant  have  not  been  investigated. 
Aro,  Richardia  jethiopica,  Kunth,  nat.  ord.  Aracese.  The  plant  is 
very  acrid  in  the  fresh  state,  the  juice  caustic,  the  leaves  and  root 
vesicating. 
Aroma,  Acacia  Farnesiana,  Willd.,  nat.  ord.  Leguminosse;  indige- 
nous to  Yucatan.  The  fruit  is  astringent  and  yields  an  extract 
known  as  jugo  de  acacia  and  having  the  same  properties  as  catechu. 
The  flowers  are  very  fragrant,  have  anti-spasmodic  properties  and  are 
much  used  in  perfumery  under  the  name  of  casia  or  cassie. 
Arrayan,  Myrtus  Arrayan,  Kunth;  indigenous  to  Mexico.  The 
