^™sepr'i885'™  }     Materia  Medica  of  the  Mexican  Pharmacopoeia,  433 
Colorin  chiquito,  Rhynchosia  precatoria,  H.  B.  K.;  Leguminosa3;  in 
Cuernavaca  and  other  hot  districts.  The  seeds  are  reniform,  somewhat 
compressed  at  the  base,  and  from  the  hilum  partly  red  and  partly 
black.  They  are  popularly  supposed  to  act  upon  the  brain,  producing 
loss  of  memory ;  but,  according  to  Dr.  Altamirano,  of  Mexico,  who 
experimented  with  the  alcoholic  extract,  this  belief  is  unfounded, 
although  toxic  principles  appear  to  exist  in  these  seeds. 
Colorin  de  peces,  Piscidia  Erythrina,  Lin.;  in  the  State  of  Guerrero. 
The  tincture  of  the  root  bark  is  recommended  for  toothache.  The 
practice  of  stupefying  fish  by  means  of  this  plant  should  be  prohibited. 
Cominos  rusticos,  the  fruit  of  a  Mexican  umbelliferous  plant ;  aro- 
matic and  resembling  fennel.  It  is  referred  to  Thapsia  Asclepium, 
Lin.  (f) ;  but  Oliva  regards  as  identical  with  it  the  fruit  which  in 
Jalisco  is  called  acocote,  and  is  derived  from  Pentacripta  atropurpurea. 
Contrayerba,  Dorstenia  Contrayerva  and  D.  Houstoni,  IJn.  ;  Morca?. 
The  former  grows  in  the  State  of  Vera  Cruz  and  other  localities,  and 
is  known  as  barbudilla ;  the  latter  is  found  in  Campeachy  and  seems 
to  be  Drake's  root.  Both  roots  are  stimulant,  diaphoretic  and  anti- 
periodic.  The  root  of  Asclepias  sestosa,  Bentham,  is  known  as  Con- 
trayerba de  Julimes,  and,  according  to  Cal,  possesses  the  same  proper- 
ties and  even  appears  to  be  superior  to  the  preceding. 
Copal,  Goma  de  limon,  from  Elaphrium  copalliferum,  Flor.  Mex. 
ined. ;  Rutacese ;  in  the  hot  regions  of  the  western  part  of  the  repub- 
lic. The  resin  is  obtained  by  incisions  made  on  the  shrub,  and  is  met 
with  in  commerce  in  semicylindrical  pieces,  brittle,  glossy,  transparent 
on  the  flat  side,  opaque  on  the  convex  side,  and  covered  with  earth ; 
it  has  a  balsamic  odor  and  an  aromatic  taste,  softens  between  the  teeth 
like  mastic,  melts  at  74°C.,  and  gradually  loses  its  transparency  and 
becomes  yellow.  It  has  the  balsamic  properties  of  similar  resins,  but 
is  not  used  in  medicine  except  as  a  substitute  for  elemi  in  ointments. 
Copalchi,  the  bitter  bark  of  various  trees,  generally  called  campa- 
nillo.  The  bark  most  commonly  met  with  is  that  of  Croton  niveum, 
Jacquin,  s.  C.  Pseudochina,  Schiede,  which  groAvs  in  Oaxaca,  Plan  del 
Rio,  Tampico,  Tehuantepec,  between  the  Laguna  verde  and  Actopan 
(where  it  is  known  as  quina  blanca,  according  to  Schiede),  in  the 
Sierra  de  San  Pedro,  etc.  Also  C.  reflexifolium,  LI.  B.  K.,  which 
grows  in  Acapulco,  Huasteca,  Paso  del  Correo,  on  the  river  Teculata, 
etc.,  and  is  often  confounded  with  the  preceding  species.  Another 
