Am.  Jour.  Pharin. 
August,  1911. 
Digitalis  Hairs. 
367 
in  some  instances  nearly  entire  leaves  it  is  for  the  most  part  made 
up  of  broken  fragments  and  the  microscopical  study  of  these  frag- 
ments is  of  the  very  greatest  interest.    There  are  a  number  of 
Fig.  I. 
Digitalis:  A,  a  typical  leaf  showing  the  winged  or  laminate  petiole  and  the  veins  of  the  first 
order  which  diverge  from  the  mid-vein  at  very  acute  angles.  B,  transverse  section  of  portion 
of  leaf  showing  the  separated  or  additional  epidermal  layer  (S);  epidermal  layer  (E);  glandular 
hair  (G);  non-glandular  hair  {N);  coUenchyma  (6^).  C,  transverse  section  near  one  of  the  veins 
showing  considerable  of  the  separated  or  extra  epidermal  layer  (5);  with  two  non-glandular 
hairs  (A^)  and  glandular  hair  (G)\  epidermal  layer  (E);  lower  epidermis  {LE)\  chlorophyll 
layer  {N) ;  upper  epidermis  (UE)\  trachea;  or  vessels  {T). 
characters  in  the  anatomy  of  this  leaf  that  might  be  studied,  but  I 
desire  at  this  time  to  call  attention  oiily  to  certain  variations  of  the 
hairs  observed  in  different  specimens,  of  the  commercial  drug  as 
also  of  the  cultivated  plants.    It  is  well  known  that  in  the  hairs 
