62  Plants  Which  in  Drying  Stain  Paper.      { AFebraarVTi™* 
given  exactly  as  I  have  worked  it  out.  In  our  school  the  method 
has  been  used  by  dozens  of  students  with  excellent  results,  but  our 
students  instead  of  using  the  U.S. P.  method  work  according  to 
directions  copied  by  the  instructors  from  my  original  article. 
Northwestern  University  School  of  Pharmacy. 
NOTES  ON  SOME  PLANTS  WHICH  IN  DRYING  STAIN 
PAPER.1 
By  J.  H.  Maiden,  Government  Botanist  and  Director  of  the  Botanic  Gardens, 
Sydney. 
Everyone  with  herbarium  experience  must  have  made  the  obser- 
vation that  some  plants  stain  the  papers  to  which  they  are  attached. 
Some,  indeed,  stain  so  persistently  (e.g.  Droseta  Whittakeri)  that  the 
coloring  matter  will  penetrate  a  dozen  sheets  or  more.  I  have 
not  observed  that  any  botanist  has  drawn  special  attention  to  the 
matter  and  do  not  know  that  any  one  has  given  an  explanation  of 
these  phenomena.  I  say  phenomena,  because  the  coloring  or 
rather  staining  may  arise  from  various  causes,  e.g.  the  presence  of  a 
specific  coloring  matter  in  the  root  or  other  portion  of  the  plant, 
or  the  formation  of  a  coloring  matter  by  oxidization  or  other 
chemical  change.  The  subject  is  of  course  one  for  a  chemist,  who 
will  subject  the  paper  itself  to  examination. 
It  will  be  observed  that  the  plants,  in  many  cases,  leave  sharp 
photographic  impressions  on  the  paper.  The  phenomena  arise  from 
an  emanation, — a  dry  distillation  possibly.  It  is  proper  to  point  out 
that  herbarium  specimens  in  the  National  Herbarium,  Sydney,  are 
protected  from  insect  ravages  by  means  of  naphthaline.  No  bichlor- 
ide of  mercury  is  used,  but  most  plants  are  placed  in  a  bisulphide 
of  carbon  chamber  before  they  are  placed  in  the  herbarium  boxes. 
Most  of  the  stains  appear  to  be  purplish,  of  varying  intensity ; 
the  remainder  are  mostly  greys  and  browns.  The  drying  black  of 
plants  which  do  not  stain  is  a  cognate  matter  which  must  not  be 
confused  with  the  subjec'  of  staining.  Many  saprophytes  and  root 
parasites  dry  black,  e.g.  Monotropa  (Monotropacese),  Gerardia  (Scro- 
1  Read  before  the  Royal  Society  of  N.  S.  Wales,  June  6,  1906,  and  reprinted 
from  Journal  and  Proceedings  of  the  Royal  Society  of  N.  S.  W.,  Vol.  XI,,  pp. 
39-45- 
