500      OBSERVATIONS  ON  SOME  PRODUCTIONS  OF  MEXICO. 
>    Pentastemon  Bentham. 
which  they  also  call  cebadilla,  and  sell  it  alone  or  mixed  with 
the  cevadilla  of  Veratrum. 
This  false  cevadilla  is  the  capsule  of  two  plants  of  the  natu- 
ral order  Scrophulariacese,  and  genus  Chelone  L.,  or  Pentastemon 
of  L'heritier  and  Endlicher.    I  characterize  them  thus  : 
1.  Filamento  sterilis  glabro. 
Chelone  gentianoides,  H.  B.  K. 
2.  Filamento  superus  barbato. 
Chelone  companulata,  Cav. 
"  These  two  plants  are  very  abundant  on  the  plateau  of 
Mexico.  The  difference  most  apparent  which  characterizes  their 
capsules,  is  that  they  are  naturally  open,  or  that  they  separate 
easily  into  four  regular  parts,  of  which  the  two  principal  divide 
a  second  time  into  two  parts ;  further,  they  have  the  hardness 
and  consistence  of  horn.  The  true  cevadilla  presents  always 
three  divisions  at  the  summit,  and  its  capsule  is  much  thinner 
and  lighter. 
"  The  seeds  of  the  false  cevadilla  are  much  smaller  and  very 
numerous ;  those  of  the  true  cevadilla  are  less  numerous,  elon- 
gated and  terminated  in  a  curved  point  at  one  extremity ;  they 
are  very  brown  and  nearly  black." 
M.  Schaffner  finally  cites  a  plant  in  the  valley  of  Mexico 
which  is  very  poisonous,  and  so  dangerous  for  cattle  that  they 
avoid  the  lands  where  it  grows  abundantly. 
It  is  the  Veratrum  frigidum  of  Schlectendahl  [Stenanthum 
frigiduW;  Kunth.)    M.  Schaffner  had  not  seen  the  capsule. 
I  will  add  that,  after  reading  this  account,  I  have  carefully 
examined  the  sabadilla  in  the  collection  of  the  School  of  Phar- 
macy, and  in  a  quantity  of  about  a  pound  have  not  found  a  single 
capsule  of  the  Scrophulariacese,  nor  but  a  dozen  brownish  cap- 
sules elliptical  and  thin,  which  may  possibly  belong  to  Veratrum 
sabadilla.  They  were  empty  of  seed,  and  I  could  observe  no 
difference  in  the  loose  seeds.  It  appears  to  me  certain  that  it 
is  the  Asagrcea  officinalis  which  furnishes,  nearly  exclusively,  the 
cevadilla  of  commerce. 
I  ought  to  mention  that  M.  Lucien  Biart,  in  his  letter  to  the 
Minister  of  Public  Instruction,  says  that  the  seeds  of  cevadilla 
participate  but  little  in  the  energetic  properties  of  the  capswle. 
This  is  contrary  to  the  received  view,  and  may  have  been 
