AmAuJo™t'  Sis™'}   Nature  and  Structure  of  Cochineal.  361 
At  one  time  Honduras  shipped  the  best  commercial  article.  At  the 
present  time,  according  to  Holmes,15  the  greater  quantity  comes 
from  Teneriffe,  one  of  the  Canary  Islands.  Other  supplies  come 
probably  from  Guatemala  and  possibly  Honduras  and  Mexico.  At 
one  time  good  cochineal  also  came  from  Vera  Cruz,  Java  and  Spain. 
According  to  the  fancy  of  the  broker  or  exporter  several  grades 
of  cochineal  are  recognized.  Holmes  says :  lt  Broadly  speaking, 
the  terms  '  Silver  grain,'  '  black  grain,'  and  '  granilla  '  are  used, 
but  there  are  intermediate  qualities  variously  designated  as  gray, 
black-gray,  silver-gray,  silver-black,  rosy-black,  red  and  foxy,  and 
these  again  may  be  qualified  by  the  terms  fair,  bold,  fine  and  so 
forth.  The  so-called  original  grains  consist  of  female  and  young 
insects,  and  the  latter  when  sifted  out  form  granilla,*  which  is  only 
worth  one-sixth  or  one-eighth  of  the  price  of  the  mature  insect. 
The  color  is  due  to  the  mode  of  preparation  for  the  market.  If 
dried  in  trays  in  the  sun,  or  in  an  oven  at  a  moderate  temperature 
(about  65 0  C.)  for  four  or  five  hours,  and  subsequently  in  the  sun, 
the  waxy  substance  is  not  melted  and  the  silver  grain  is  the  result. 
If  they  are  dried  at  a  higher  temperature  than  1060  C,  the  melting 
point  of  the  wax  on  hot  iron  plates,  the  black-grain  is  the  result. 
The  red  tint  of  the  rosy-black  is  said  to  be  produced  if  they. are  put 
in  bags  and  dipped  in  boiling  water  to  kill  them  before  drying,  and 
that  of  the  foxy  silver  grain  is  produced  by  sifting  the  insects 
when  not  perfectly  dried  so  that  some  of  the  coloring  matter  tinges 
the  surface.  The  black  grain  usually  obtains  a  higher  price  than 
the  silver  grain.  Both  the  black  and  silver  grain  are  sometimes 
adulterated  to  meet  the  demand  for  a  cheap  article.  The  black 
grain  is  sometimes  met  with  having  the  concave  side  filled  with 
grains  of  a  magnetic  iron  sand.  The  silver  grain  is  said  to  be 
weighted  with  sulphate  of  barium  or  carbonate  of  lead  and  the 
very  white  appearance  is  given  by  powdered  talc  or  other  white 
powder." 
These  facts  with  regard  to  the  preparation  of  the  commercial 
article  are  given,  as  a  knowledge  of  these  will  readily  explain  why 
*  The  commercial  variety  known  as  "  granilla "  represents  probably 
nothing  more  than  the  smaller  females  in  which  the  larvae  have  shown  but 
a  very  slight  development.  It  is  self-evident  from  what  has  been  stated  in 
this  paper  that  the  larvae  are  enclosed  in  the  abdomen  of  the  mother  insect 
and  could  not  be  separated  by  sifting.  This  view  is  also  supported  by  the 
observations  of  G.  A.  Shaw.18 
