CULTURE  OF  COCHINEAL  IN  THE  CANARY  ISLANDS.  437 
moved.  They  are  distinguished  from  the  flattened  shoot  of  the 
young  leaves  by  their  round  form. 
The  cochineal  insect  should  only  be  placed  upon  plants  three 
or  four  years  old.  During  the  first  year,  potatoes  or  barley  may 
be  grown  in  the  space  between  the  furrows,  but  afterwards  this 
must  be  discontinued,  so  as  not  tc  interfere  with  the  roots  of  the 
nopal. 
In  autumn  the  yellow  leaves  are  removed.  Good  nopal  serves 
for  twelve  or  fourteen  years  for  the  culture  of  cochineal.  In  the 
months  of  March,  April,  or  May,  according  to  the  season,  the 
young  broods  are  placed  upon  the  leaves.  In  warm  weather, 
they  are  hatched  on  the  seventy-fifth  or  ninetieth  day  ;  in  cold 
weather,  ninety-three  or  one  hundred  and  thirteen  days  are  re- 
quisite. Those  who  are  experienced  in  the  matter,  believe  they 
can  predict  the  day  that  the  young  brood  will  be  hatched.  So 
soon  as  they  begin  to  move,  the  mother  insects  are  carefully 
collected  and  spread  out  about  an  inch  apart  on  boards  in  boxes. 
The  cochineal  are  covered  with  rags  an  inch  wide,  and  four  or 
five  inches  long.  These  rags  must  not  be  larger,  because  when 
the  leaves  are  overloaded  with  insects,  they  remain  small  and 
weak.  Moreover,  the  females  are  then  less  productive,  the  leaves 
are  consumed  more  rapidly,  and  the  expenses  proportionately  in- 
creased. The  rags  are  removed  from  the  cochineal  daily,  or 
even  more  frequently,  and  when  they  are  sufficiently  covered 
with  the  young  insects,  they  are  carried  in  a  basket  to  the  nopal, 
each  rag  laid  upon  a  leaf,  and  fastened  with  the  thorns.  After 
a  few  days,  when,  the  insects  have  spread  themselves  over  the 
leaf,  the  rags  are  removed.  The  opinion  that  it  is  better  not  to 
place  the  insects  upon  the  plants  for  at  least  six  days,  appears 
to  be  simply  founded  on  prejudice,  and  is  not  confirmed  by  ex- 
periment. 
Instead  of  the  rags,  small  bags  of  muslin  are  sometimes  used  ; 
a  number  of  mother-insects  are  placed  in  each  bag,  which  is  hung 
upon  the  nopal  leaves  until  the  young  are  hatched,  and  the  in- 
sects have  crawled  up  on  the  leaves.  Many  insects  are  lost  in 
this  way,  and  it  has  also  the  inconvenience  that  the  whole  brood 
comes  upon  one  part  of  the  leaf,  and  their  development  is  re- 
tarded. 
When  the  young  are  hatched,  the  mother-insects  which  ap- 
