CULTURE  OF  COCHINEAL  IN  THE  CANARY  ISLANDS.  435 
3.  Lanzaroti  Here  the  culture  of  the  cactus  is  very  ex- 
tended.  It  grows  with  great  luxuriance  and  rapidity,  and  the  cul- 
ture of  cochineal  is  carried  on  with  great  success, 
4.  Gomera. — Here  the  attempts  to  establish  this  industry  have 
been  less  successful. 
It  is  likewise  stated  that  the  Indian  fig  grows  well  upon  Gran 
Canaria,  but  no  mention  is  made  of  the  culture  of  cochineal 
there. 
In  Palma,  the  sixth  island,  the  production  of  silk  appears  to 
be  more  extensively  carried  on  ;  and  in  Hieroo,  the  deficiency 
of  springs  may  render  the  culture  of  the  cochineal  insect  or  of 
cactus  impossible. 
It  is  also  stated  that  there  are  in  the  Canaries  three  concentric 
zones.  The  first,  costa,  extends  about  a  league  from  the  coast 
inland,  becomes  wider  when  the  surface  is  even,  narrower  when 
it  is  hilly.  The  intermediate  zone,  mediania,  extends  as  far  as 
the  foot  of  the  mountains  in  the  centre  of  the  islands,  and  the 
cumbres  comprises  the  mountainous  districts. 
These  remarks  are  necessary,  in  order  to  render  what  follows 
intelligible  ;  and  it  may  be  added  that  it  is  D.  Santiago  de  la 
Cruz  who  has,  with  much  trouble,  introduced  the  culture  of  cochi- 
neal into  the  Canaries. 
There  are  several  species  of  nopal^  la  tunera  silvestre  Indian  fig, 
cactus  tuna,  short  leaf  with  numerous  thorns,  serve  only  for 
coloring  sugar,  fruit,  and  wafers  ;  and  la  tunera  amarilla,  with 
large,  yellow,  sweet  fruit,  and  round  green  leaves.  The  tunera 
blanca  is  best  adapted  for  the  culture  of  cochineal ;  but  it  is  in- 
convenient, on  account  of  its  numerous  thorns.  Lastly,  there  is 
a  Mexican  species  with  very  soft  thorns,  which  is  likewise  avail- 
able for  cochineal  culture. 
In  planting  the  nopal,  land  must  be  selected  which  is  exposed 
to  the  sun  and  sheltered  from  wind,  so  that  the  insects  may  not 
be  blown  off  the  leaves.  The  soil  must  not  be  close  and  clayey, 
but  light  and  porous  ;  so  that  the  roots  may  easily  penetrate 
downwards,  and  the  moisture  be  retained  within  it.  The  soil  may 
be  stony,  and  the  plants  may  even  be  set  upon  the  bare  rock, .if  there 
are  any  fissures  into  which  the  roots  can  penetrate.  When  they 
are  planted  upon  the  plain,  the  soil  must  be  ploughed  up  at  least 
a  foot  and  and  a  half  deep.    The  plants  are  set  in  the  furrows  at 
