and  the  Prevention  of  Rot. 
277 
and  a detailed  account  intended  for  scientific  readers  was  pub- 
lished in  the  ‘ Quarterly  Journal  of  Microscopical  Science  ’ for 
January  1883.  To  this  last-named  paper  I may  refer  any 
reader  who  desires  to  learn  the  details  of  the  development  of 
the  liver-fluke.  The  present  paper  is  only  intended  to  give 
the  outlines  of  the  life-history  of  the  fluke  in  such  a way  as  to 
enable  the  farmer  and  the  general  reader  interested  in  agri- 
cultural matters  to  understand  how  the  parasite  is  propagated 
through  successive  generations,  how  the  sheep  incurs  the  disease 
by  taking  in  the  young  fluke  with  its  food,  and,  lastly,  the 
various  methods  of  preventing  the  spread  of  so  destructive  a 
disease.  Technical  terms  will  therefore  be  purposely  avoided. 
For  the  sake  of  convenience  the  subject  is  divided  into  the 
following  parts  : — 
I. — Nature  of  the  Disease. 
II. — Life-history  of  the  Liver-fluke. 
III. — Prevention  of  the  Rot. 
Part  I. — Nature  of  the  Disease. 
The  Rot,  liver-rot,  fluke  disease,  coathe,  or  bane,  are  all  names 
given  to  one  and  the  same  disease.  It  is  sometimes  known  as 
the  sheep-rot,  since  amongst  our  domesticated  animals  the  sheep 
is  by  far  the  most  frequent  victim.  Very  many  other  animals 
that  eat  grass  or  herbs  are,  however,  subject  to  the  disease, 
including  cattle,  deer,  horses,  pigs,  rabbits,  hares,  kangaroos, 
camels,  &c.  ; and  even  man  himself  is  occasionally  attacked. 
Liver-rot  has  been  known  and  dreaded  from  very  early  times; 
it  was  so  well  known  in  Shakspeare’s  day  that  an  allusion  to  it 
occurs  in  his  writings.  It  is  unnecessary  for  me  to  enter  here 
into  a history  of  the  disease  ; for  this  I may  refer  to  Professor 
Simonds’s  paper.* 
Many  theories  have  been  suggested  as  to  the  cause  of  the 
disease,  several  of  them  being  very  far  from  the  truth.  It 
is  really  a parasitic  disease,  and  is  caused  by  the  presence, 
in  the  bile-ducts  of  the  liver  of  the  diseased  animal,  of  large 
numbers  of  a flat  worm,  known  as  the  liver-fluke  (called  by 
zoologists  Fasciola  hepatica,  or  less  correctly,  Distoma  hepaticum). 
The  liver-fluke  has  the  shape  of  a privet-leaf,  or  of  a small  sole ; 
it  is  pale  brown  or  of  a flesh-colour,  and  is  about  an  inch  or 
an  inch  and  a third  in  length,  and  in  breadth  about  half  its 
own  length.  At  one  end  is  a narrower  projecting  portion, 
which  may  be  compared  to  the  short  thick  stem  of  the  leaf; 
* “The  Rot  in  Sheep.”  London,  John  Murray,  1880.  See  also  ‘Journal  of 
the  Royal  Agricultural  Society,’  Second  Series,  vol.  xvi.  Part  I.,  1880,  p.  121. 
