AmiifS  i9i3rm' }  Nature  and  Structure  of  Cochineal.  347 
from  thence  certain  maggots  or  aurelias  which  changed  into  flies ;  that 
these  flies .  settling  on  the  trees  were  then  killed  by  making  fires  under  the 
trees,  the  smoke  of  which  caused  them  to  fall  down ;  after  which  they  were 
stripped  of  their  heads,  the  fore  parts  of  their  bodies,  and  their  wings,  and 
the  remainder  preserved  for  use,  so  that  cochineal  was  properly  and  in 
truth  the  hinder  part  or  tail  of  a  fly,  and  consequently,  that  my  observations 
were  so  far  correct  that  the  substance  I  had  seen  were  really  eggs,  such  as 
are!  found  in  the  hinder  part  of  the  silk-worm's  moth.* 
"  To  this  I  replied,  that  in  my  preceding  observations,  it  was  impossible 
for  me  to  judge,  that  cochineal  was  an  animal  substance,  because  there 
was  nothing  to  be  seen  in  it  that  resembled  an  animalcule,  and  I  concluded 
that  if  it  had  been  an  animal,  it  would  have  been  devoured  by  those  animal- 
cules, called  mites ;  and  I  added,  that  in  consequence  of  the  information  com- 
municated by  the  Honorable  Mr.  Boyle,  in  his  letter  I  had  repeated  my 
observations,  the  result  of  which  as  I  communicated  them  to  him  is  as  follows : 
"  On  this  renewed  investigation  of  the  subject,  I  was  fully  convinced 
that  every  single  grain  of  cochineal  was  part  of  an  animalcule  from  which 
not  only  the  head,  the  fore  part  of  the  body,  and  the  wings,  had  been  broken 
off,  but  that  also  the  legs,  and  that  part  of  the  body  to  which  the  legs  are 
joined  had  been  thrown  away,  so  that  nothing  was  left,  except  the  animal's 
hinder  part;  and  I  imagined  that  the  colorless  substance  before  mentioned, 
and  which  was  to  be  observed  in  the  chinks  or  creases  in  every  grain,  was 
some  preparation,  applied  to  the  cochineal,  when  it  is  collected  for  sale,  to 
defend  it  from  mites,  which  otherwise  would  destroy  or  devour  it. 
"  These  creases  or  rings,  in  every  grain  of  cochineal,  I  imagine  are, 
the  articulates  or  joints,  in  those  kinds  of  maggots  or  caterpillars,  which 
afterward  change  into  a  flying  insect ;  and  I  did  not  doubt,  that  at  the  proper 
season,  when  a  similar  kind  of  insect  could  be  found  in  this  country  I  should 
establish  the  fact,  allowing  only  for  the  difference  for  shape  and  color  between 
them,  and  those  which  constitute  cochineal." 
He  then  goes  on  to  say  that  he  examined  a  large  parcel  of  cochi- 
neal and  found  in  it  several  of  the  shells  or  coverings  of  the  wings, 
which  shells  were  of  a  black  color,  with  each  a  red  spot  in  the 
middle.  He  also  mentions  finding  fragments  of  what  he  terms 
aurelias  which  he  concluded  were  formed  from  the  maggots  or 
caterpillars  of  this  species,  and  in  one  of  them  was  a  piece  of  a 
maggot,  which,  in  part,  seemed  to  have  been  devoured  by  a  mite. 
*  It  is  doubtful  if  by  the  methods  that  Leeuwenhoek  used  in  clearing 
his  material  that  he  actually  saw  the  eggs  or  larvae.  Certainly  if  he  was  able 
to  see  the  larvae  he  would  have  seen  the  mouth  parts  and  legs  of  the  mother 
insect  and  not  come  to  the  conclusion  that  the  cochineal  of  commerce  repre- 
sented only  the  hind  portions  of  the  insect.  This  may  be  readily  confirmed 
by  examining  the  microphotographs  of  the  cochineal  of  commerce,  Figs. 
2  and  3. 
