AmAp°rnr;Srm"}  Immunity  to  Poisons.  171 
l/   IMMUNITY  TO  POISONS. 
By  WmiAM  B.  Thompson. 
The  remarks  of  the  editor  of  this  Journal  on  the  apparent  im- 
munity of  fowls  from  the  toxic  action  of  drugs  prompts  the  follow- 
ing thoughts : 
The  immunity  of  certain  animals  to  the  action  of  poisons  and  of 
poisonous  drugs,  finds  an  analogy  to  some  extent  in  the  resistance 
which  the  insect  tribe  appear  to  have  against  the  acrid,  irritant  and 
destructive  character  of  many  substances.  Take  the  well-known 
ravages,  in  depredation,  upon  cantharides,  capsicum,  et  al.  The 
impunity  shown  is  a  marvel  to  the  understanding.  These  animate 
creatures,  large  and  small,  obey,  of  course,  one  common  implanted 
instinct,  namely,  the  quest  for  food.  Although  they  may  not 
always  be  revelling  in  the  choice  of  their  pabulum,  they  have  a 
faculty  of  .adapting  circumstances  to  their  wants  and  of  securing  a 
supply  from  one  source  or  another.  It  is  a  puzzle  to  our  minds 
that  they  continue  to  exist  and  flourish  when  our  more  acute  senses 
revolt  and  our  sense  of  danger  cautions.  The  benign  Creator  has 
withheld  from  these  creatures  a  keen  sense  of  discrimination  be- 
tween the  hurtful  and  the  harmless,  and,  therefore,  as  a  compensa- 
tion, perhaps,  he  may  have  constituted  the  lower  orders  less  vul- 
nerable to  the  action  of  poisons. 
Animals,  generally,  are  not  endowed  with  a  premonitory  sense  of 
danger,  therefore  they  do  not  have  this  safeguard  so  inestimable  to 
our  lives.  The  lamb  follows  the  executioner  to  the  slaughter,  un- 
conscious of  impending  death,  although  the  fatal  axe  may  be  swing- 
ing in  full  view  of  the  beast. 
The  immunity  of  fowls  (if  credibly  ascertained)  against  the  toxic 
action  of  nux  vomica,  is  not  readily  explained,  because  their  processes 
and  function  of  digestion  and  assimilation  are  quite  similar  to  ours, 
— consider  the  rigid,  muscular  strength  of  the  gizzard.  It  would, 
therefore,  seem  that  there  is  the  same  general  provision  in  this 
case  for  the  decomposition  of  food  as  exists  in  the  carnivora,  or 
as  in  man,  with  his  varied  and  miscellaneous  diet.  Digestion  and 
excretion  are  far  more  rapid  in  the  lower  than  in  the  higher  class 
of  animals,  notably  in  birds.  The  separation  of  that  which  is  re- 
quired from  that  which  is  valueless  is  a  rapidly  performed  process 
in  the  former,  and  we  assume  that  the  fact  is  established  that  the 
carnivora  are  much  more  susceptible  to  the  action  of  poisons  than 
