344 
Powdered  Drugs  under  the  Microscope. 
Am.  Jour.  Pharne 
Aug.,  1876. 
toadstool-like,  takes  place  as  the  powder  becomes  old  and  dried.  The 
diameter  of  the  glands  is  about  j$tt. 
Along  with  these  glands  are  found  fragments  of  the  surface  mem- 
brane (epidermis),  scraped  off  with  them.  The  figure  shows  a  frag- 
ment of  this  epidermis,  with  its  cells  and  breathing  pores.  Separate 
fragments  of  resin,  with  occasional  crystals  of  the  same,  are  found. 
Hairs  from  the  hop  are  also  sometimes  present. 
The  fragments  of  epidermis  and  hairs  are  impurities,  and  should  not 
be  abundant.  Lupulin  sometimes  contains  sand.  This  can  be  easily 
separated  by  water,  in  which  the  powder  floats,  while  the  sand  sinks. 
When  the  grains  have  so  far  dried  as  to  become  toadstool-shaped,  and. 
orange-yellow  in  color,  the  powder  has  lost  its  valuable  properties. 
2.   LYCOPODIUM  (Fig.  8). 
This  is  a  very  fine  and  volatile  powder,  made  up  of  the  spores  (seed- 
like bodies)  of  the  common  northern  club  moss  (Lycopodium  clavatum). 
The  powder  is  of  a  light  yellow  color,  odorless  and  without  taste.  It 
does  not  mix  with  water,  but  readily  mingles  with  alcohol,  ether,  chlo- 
roform, etc.  Thrown  into  a  flame,  it  flashes  brightly,  but  in  the  mass 
it  does  not  fire  readily.  It  does  not  turn  blue  with  iodine,  nor  with; 
iodine  and  sulphuric  acid. 
Each  grain  or  spore  is  a  three-sided  pyramid,  with  a  convex  base. 
It  looks  as  if  it  was  cut  out  of 
a  sphere  by  three  planes,  each 
of  which  passed  through  the 
center.  In  one  of  the  grains 
represented  in  the  figure  we  are 
looking  directly  down  on  the 
apex  of  the  pyramid.  In  two 
of  the  others,  we  view  the  pyr- 
amid a  little  from  one  side.  In 
the  remaining  two,  we  are  look- 
ing at  the  convex  base  of  the 
grain.  A  groove  runs  down 
each  angle  from  the  apex.  The 
0  T         ..  true  nature  of  the  markings  on, 
Pig.  8.  Lycopodium.  0 
the  surface  cannot  be  made  out 
without  some  care.    When  carelessly  focussed,  the  grains  appear  to 
be  covered  with  hairs  of  peculiar  shape,  better  seen  at  the  edges.  If 
