NOMENCLATURE,  ETC.,  IN  THE  MATERIA  MEDICA,  U.  S.  P.  521 
or  the  two  together,  the  roots  occupying  the  smaller  bulk.  The 
term  rhizome  is  used  eleven  times  in  our  Pharmacopoeia,  and 
always  in  consonance  with  this  rule.  Calamus,  curcuma,  iris 
florentina,  iris  versicolor,  podophyllum,  sanguinaria,  veratrum 
album  and  zingiber,  occur  in  commerce  mostly  entirely  destitute 
of  roots  ;  while  geranium  and  veratrum  viride  usually  have  the 
rootlets  attached,  and  filix  mas,  besides  the  small  adventitious 
roots,  is  covered  with  the  base  of  the  stipes  closely  overlapping 
each  other.  Among  those  drugs  which  the  pharmacopoeia  de- 
fines as  roots,  we  meet  tormentilla  in  the  market  almost  or 
entirely  free  from  rootlets  ;  cimicifuga,  helleborus,  hydrastis, 
leptandra  and  some  others  have  large  rhizomes  and  small  roots 
as  compared  with  the  size  and  bulk  of  the  former.  Goldthread, 
though  defined  as  the  root  of  Coptis  trifolia,  always  consists  of 
the  entire  plant,  which,  as  met  with  in  commerce,  has  many  leaves 
and  but  few  small  rootlets,  the  underground  portion  consisting 
mainly  of  the  long  golden  yellow  thread-like  rhizome. 
Jalap  has  a  globular  rootstock  entirely  free  from  leaf  scars, 
and  below  suddenly  contracted  into  one  or  sometimes  two  long, 
rather  thin,  somewhat  branching  roots,  which  in  the  commercial 
article  have  been  almost  completely  removed.  Several  stems 
are  produced  which  often  form  long  runners  and  are  then  beset 
with  smaller,  more  oblong  tubers,  which  otherwise  are  of  the 
same  structure  as  the  main  one ;  this  occasionally  sends  off 
branches,  which  again  swell  into  tubers.  From  this  description, 
which  is  taken  from  Fllickiger's  Pharmakognosie,  it  is  very 
apparent  that  jalap  must  indeed  be  regarded  as  a  tuber  and  not 
as  a  root. 
Aconitum  napellus  grows  from  a  small  napiform  tuber  which 
produces  one  or  more  short  branches,  the  last  nodes  of  which 
enlarge  to  tubers  of  the  same  shape  ;  in  commerce  we  frequently 
find  two  or  three  still  united,  or  if  separate,  the  very  short 
rhizomes  are  usually  attached  to  some,  or  at  least  the  scars  are 
visible  where  the  rhizomes  have  become  detached. 
The  term  conn  is  sometimes  made  to  include  almost  all  forms 
of  short  and  thick  underground  stems  and  buds,  except  the 
foliaceous  and  scaly  bulb  ;  but  the  true  scientific  definition 
makes  it  a  solid  bulb,  that  is  a  plantiparous  bud  with  a  con- 
