and  the  Prevention  of  Rot. 
287 
shown  in  Fig.  7.  This  is  worthy  of  mention  here,  as  it  causes 
a still  greater  increase  in  the  number  of  the  parasites  within 
the  snail. 
Tig.  7. 
A young  sporocyst  dividing  into  two: 
A',  eye-spots  disappearing.  Magnified 
500  times.  (Original. — A.  P.  T.) 
Fig.  8. 
A full-grown  sporocyst  (the  first  genera- 
tion) of  the  Liver-fluke.  It  contains 
several  germs  in  different  stages  of 
growth.  The  largest,  at  the  lower  end, 
has  assumed  the  coaracters  of  a redia. 
Magnified  230  times.  (Original. — 
A.  P.  T.) ' 
Let  us  return  to  the  rediae  which  compose  the  second  genera- 
tion. Figs.  9 and  10  (p.  288)  show  two  free  rediae  ; the  former 
is  nearly  half  grown,  and  the  latter  is  adult.  The  rediae  are  much 
more  active  than  their  parents,  and  migrate  from  the  lung  into 
the  other  organs  of  the  snail,  and  particularly  into  the  liver, 
