AmMa"x879arm  }      Poisonous  Species  of  Astragalus.  '  237 
This  lead  me  to  experiment  upon  the  subject,  although  it  certainly- 
seemed  natural  to  accept  without  question  a  general  conclusion.  [ 
believe  in  similar  cases  that  light  influences  the  change. 
The  experiments  instituted  for  the  purpose  of  testing  the  accuracy 
of  the  light  hypothesis  contradict  it  most  positively.  In  similar  inves- 
tigations with  other  substances,  I  have  been  compelled  to  admit  that 
light  has  little  if  any  influence.  So  with  this;  the  light  as  a  coincidence 
only  happens  to  strike  upon  the  portion  of  the  vessel  where,  under 
natural  laws  which  govern  the  deposition  of  this  substance,  the  pre- 
cipitate will  form. 
This  article  is  not  intended  as  an  argument  upon  Nature's  laws  and 
the  phenomena  which  accompany,  however  interesting  they  may  be; 
therefore,  I  will  not  consume  time  with  the  experiments. 
Cincinnati,  Ohio,  April  15th,  1879. 
POISONOUS  SPECIES  OF  ASTRAGALUS. 
By  John  M.  Maisch. 
The  April  number  of  the  "  Pacific  Medical  and  Surgical  Journal" 
contains  a  paper  by  D.  H.  Gibbons,  Sr.,  on  the  "Poisonous  Effects  of 
Crotalaria — vulgo  Rattle  Weed,  Loco  Weed  " — in  which  the  effects  of 
the  plant  on  horses  and  sheep  are  described.  These  are  indicated  to 
some  extent  by  the  name  (loco  weed)  given  to  the  plant  by  the  native 
population,  the  term  loco  indicating  insanity  or  madness.  The  plant 
in  question  is  described  as  follows  : 
"  The  plant  grows  abundantly  in  almost  all  parts  of  California,  and 
may  be  easily  distinguished  by  its  bunches  of  inflated  seed  vessels,  each 
of  which  is  an  oval  bladder  about  an  inch  in  length,  or  about  the  size 
of  a  chestnut.  The  seeds  occupy  but  a  small  portion  of  the  bladder, 
and  when  the  clusters  are  trodden  on  there  is  quite  an  explosion.  The 
plant  mostly  has  flowers  and  full-grown  seed-pods  at  the  same  time, 
and  continues  in  bloom  from  spring  to  autumn.  It  grows  from  one  to 
three  feet  high,  and  is  commonly  much  branched  from  the  root.  The 
flowers  are  white,  or  greenish-white,  and  in  long,  erect  racemes.  The 
leaves  are  pinnate  and  rather  handsome." 
The  botanical  name  of  the  plant  is  not  given,  but  since  the  descrip- 
tion of  the  seed  vessels  corresponds  with  the  general  appearance  of  the 
inflated  legumes  of  the  genus  Crotalaria^  it  was  at  first  supposed  that 
