Am.  Jour.  Pharm. 
July,  1S97. 
Insect  Powders  of  Commerce. 
359 
CHEMICAL  COMPOSITION. 
The  specimen  used  in  this  investigation  was  obtained  from  the 
Highlands  Nursery,  near  Kawana,  North  Carolina.  No  published 
record  can  be  found  of  an  examination  into  the  composition  of  any 
part  of  this  tree.  The  leaves,  the  stem  bark  and  the  root  bark  were 
partly  examined  with  the  following  results  : 
Ash  in  absolutely   Tannin  in  absolutely 
Moisture.      dry  material.  dry  material. 
Leaves  7*07  270  .  4*52 
Stem  bark  .  .  8 -22  1*44  18*35 
Root  bark  5'95  2*20  17  02 
The  ashes  of  these  several  parts  contained  potassium  and  calcium  as 
phosphates  and  carbonates,  and  silica ;  besides  these,  the  ashes  of 
both  barks  contained  sulphates.  No  further  investigation  was  made 
of  the  tannin,  but  it  is  safe  to  predict  its  identity  with  that  from  the 
other  species. 
ECONOMICS. 
On  account  of  the  scarcity  of  this  tree,  it  does  not  appear  to  have 
been  put  to  any  practical  use,  although  a  comparison  indicates  that 
it  could  be  applied  to  all  the  uses  now  possessed  by  the  common 
hemlock. 
INSECT  POWDERS  OF  COMMERCE.1 
By  George  Reynolds  Durrant. 
During  the  past  quarter  of  a  century  at  least  twenty  eminent 
chemists,  pharmacists,  and  microscopists  have  devoted  some  atten- 
tion to  the  physical  characteristics,  chemical  constituents,  and  toxic 
properties  of  the  insect  powders  of  commerce.  In  the  earlier  part 
of  this  period  the  references  were  exclusively  to  the  powder  from 
the  flowers  of  Crysanthemum  caucasicum,  or  Persian  variety,  which 
gradually  gave  way  to  the  Dalmatian  kind  produced  from  the 
flowers  of  the  Crysanthemum  cinerarisefolium,  and  it  is  possible  that 
the  Dalmatian  replaced  the  Persian  variety  because  the  latter  was 
the  first  kind  to  be  grossly  adulterated ;  at  least  it  is  true  in  my 
experience  that  both  kinds  are  equally  useful  if  equally  free  from 
sophistication. 
A  careful  study  of  the  whole  of  the  subject  is  more  likely,  in  the 
absence  of  much  personal  experiment  and  thought,  to  confuse  the 
1  Pharmaceutical  Journal,  June  12,  1897. 
