4 
Belladonna  and  Hyoscyamus. 
f  Am.  Jour.  Pharm. 
\    January,  1915. 
copoeia  appears  only  in  young  leaves,  and  is,  besides,  too  rare  to 
serve  as  a  basis  of  recognition.  I  have  studied  the  presence  of 
these  crystals  of  calcium  oxalate  during  the  entire  life  history  of 
Hyoscyamus,  and  I  find  that  sphenoidal  crystals  occur  during  all 
stages  of  growth.  The  sphenoidal  crystals  I  have  found  in  the  young 
leaves  and  also  in  the  mature  leaves.   The  sphenoidal  crystals  occur 
Fig.  7. — Branching  hairs  found  in  the  different  forms  of  Hyoscyamus  niger  and  in  H.  albus. 
in  a  few  cells  of  the  parenchyma  layers  immediately  surrounding 
the  vascular  bundle  of  the  midrib.  The  average  transverse  section  of 
a  mature  leaf  contains  from  ten  to  fifteen  cells  with  sphenoids.  The 
crystals  vary  in  size  from  three  to  ten  microns  long.  The  number 
of  these  crystals  in  powdered  Hyoscyamus  is  not  great,  but  they  are 
always  present. 
