322 
bisects  Injurious  to  Drugs. 
Am.  Jour.  Pharixi. 
July,  1893. 
this  time,  Prof.  Kellogg  and  Mr.  S.  J.  Hunter  have  continued  this 
study,  to  whom  I  am  indebted  for  the  material  contributed  upon 
the  subject  at  the  last  meeting  of  this  Association.  I  shall  in  this 
article  briefly  glance  at  the  various  insects  themselves  found  in 
various  drugs  and  make  some  comments  upon  them  for  the  better 
understanding  of  them. 
Referring  now  to  Plate  I,  I  will  call  attention  to  Fig.  10.  The 
natural  size  of  this  mite  is  found  in  Fig.  ioa.  This  is  the  common 
cheese,  or  flour  mite,  familiar  to  most  of  us,  found  in  farinaceous 
drugs.  The  order  to  which  it  belongs — the  mites — are  characterized 
by  having  most  of  the  mouth  parts  united  to  form  a  piercing  beak. 
They  have  two  sharp  needle-like  projections  which  correspond  to 
the  jaws  or  mandibles  of  other  insects.  These  stylets  or  lancets  are 
very  useful  when  the  mite  needs  to  pierce  some  protecting  envelope 
to  get  at  succulent  inner  matter,  or  when  the  mite  has  to  live  on  "dry 
food."  This  mite  species  lives  on  raw  sugars,  in  which  it  appears 
as  small  white  specks.  At  least  a  half  dozen  species  of  mites  attack 
cantharids,  which,  we  know,  are  insects  belonging  to  the  great- 
beetle  order.  Besides  the  mites,  several  species  of  small  animal 
eating  beetles  do  great  havoc  in  the  jars  of  cancharids.  The  beetles 
of  the  dermestid  family,  to  which  belongs  the  well-known  buffalo 
bug,  or  moth  of  the  household,  feed  almost  exclusively  on  the  dried 
remains  of  animals ;  at  least  this  is  their  food  when  in  the  young  or 
grub  state.  Right  here  it  may  be  well  to  interpose  a  few  remarks 
upon  certain  peculiarities  in  the  life  history  of  insects,  the  knowl- 
edge of  which  is  essential  to  the  intelligent  comprehension  of  the 
subject  in  hand. 
While  in  certain  groups  of  insects  the  young  when  hatched  from 
the  egg  (and  insects  are  hatched  from  eggs,  almost  without  excep- 
tion) resemble  the  parents,  the  adults,  yet,  in  other  groups  or  orders, 
as  the  beetles,  the  two-winged  flies,  the  butterflies  and  moths,  and 
the  ants,  bees  and  wasps,  the  young  appear  in  wholly  different  form 
from  that  which  they  will  assume  when  full  grown.  For  example, 
in  the  beetles,  you  remember,  we  had  come  to  the  consideration  of 
certain  cantharid-eating  beetles,  the  first  stage  after  leaving  the  egg 
is  that  of  a  grub  or  worm,  so-called.  This  worm-like  stage  is  called 
the  larval  stage,  and  the  insect  itself  a  larva,  in  the  case  of  the 
dermestid  beetles,  of  which  several  kinds  infest  the  cantharids,  the 
larva  is  a  peculiarly  hairy  grub,  well  shown  in  the  accompanying 
