368  Assay  of  Belladonna  Root.  lA  aS.mST0" 
CRYSTALS. 
Crystals  of  calcium  oxalate  are  abundant,  and  are  found  in  all 
parts  of  the  plant.  They  are  in  the  form  of  pyramids,  prisms  and 
rosette- shaped  aggregates  (Fig.  5,  N).  The  aggregate  crystals, 
which  often  measure  forty  to  sixty  microns  in  diameter,  occur  for  the 
most  part  in  the  cortex  of  the  stems,  and  are  relatively  few  in  num- 
ber. The  prismatic  and  pyramidal  forms,  measuring  four  to  fifty 
microns  in  diameter,  frequently  occur  as  twin  crystals,  and  stand 
out  prominently  in  any  mounted  preparation,  whether  it  be  made 
from  material  in  the  form  of  powder  or  from  sections. 
A  comparison  of  Hyoscyamus  muticus  with  the  official  Hyoscyamus 
niger  brings  out  characteristics  which  cannot  fail  to  distinguish  the 
two  drugs.  The  much  lighter  and  yellowish  color  of  Hyoscyamus 
muticus;  the  larger  and  more  conspicuous  stem  remnants  and 
calyces  furnish  diagnostic  characters,  which  even  to  the  unaided  eye 
are  reliable  means  of  identification.  A  microscopical  examination, 
however,  shows  even  more  striking  diagnostic  characters.  The 
trichomes  of  Hyoscyamus  muticus  stand  out  as  the  most  prominent 
and  reliable  diagnostic  character  that  distinguishes  the  two  species. 
But  other  characters  almost  as  important  are  found  in  the  epidermal 
cells  of  both  leaves  and  calyces,  the  wood  fibers,  the  crystals,  the 
large  parenchyma  cells  of  the  cortex,  and  the  very  conspicuous 
cells  of  the  testa. 
THE  ALKALOIDAL  ASSAY  OF  BELLADONNA  ROOT. 
By  W.  A.  Pearson  and  J.  G.  Roberts. 
Owing  to  the  variation  between  our  results  and  those  of  Dr.  Carl 
Enoch,  of  Hamburg,  Germany,  as  to  the  alkaloidal  content  of  cer- 
tain shipments  of  belladonna  root,  both  our  method  and  that  of  Dr. 
Enoch  were  critically  examined  and  compared. 
Dr.  Enoch  was  kind  enough  to  give  us  the  complete  details  of 
his  method,  which  is  a  modification  of  Keller's,  and  is  as  follows  : 
"The  root,  after  being  carefully  dried,  is  powdered  medium 
finely  and  12  grammes  are  placed  in  a  glass-stoppered  Erlenmeyer 
flask  of  about  200  c.c.  capacity,  and  exactly  90  grammes  of  ether 
and  30  grammes  of  chloroform  are  added.  After  inserting  the  glass 
stopper  securely,  allow  the  flask  to  stand  ten  minutes,  so  that  the 
