382  The  Making  of  an  Herbarium.  {AmjJu°1^1&6arm- 
sorbent  cotton  should  be  placed  in  them  to  facilitate  drying,  and  to 
preserve  their  outlines. 
Specimens  should  be  dried  as  rapidly  as  possible,  to  preserve  their 
color  and  general  appearance,  and  the  driers  should  be  changed 
every  day  for  five  days ;  still  better  results  will  be  obtained  by 
changing  them  two  or  three  times  during  the  first  twenty-four  hours. 
According  toSchroeder  (Amer.  Jour.  Pharm.,  1896,  p.  132),  heavy 
gray  felt  paper,  saturated  with  a  3  per  cent,  solution  of  oxalic  acid 
and  allowed  to  dry,  will  preserve  unchanged  the  color  of  the  petals, 
and  in  most  cases  the  green  of  the  leaves. 
When  the  plants  are  thoroughly  dried  they  should  be  poisoned 
by  applying  a  nearly  saturated  solution  of  corrosive  sublimate  with 
a  soft  brush,  the  plants  being  laid  upon  a  flat  dish,  and  afterwards 
placed  between  driers  until  the  alcohol  evaporates. 
Then  follows  the  mounting  of  the  specimens.  Sheets  of  white 
paper,  1 1  y2  x  17^  inches,  about  30  pounds  to  the  ream  of  480  sheets, 
are  best  for  this  purpose.  They  should  be  fastened  to  the  sheets 
either  by  narrow  strips  of  isinglass  plaster,  or  better,  directly  by 
means  of  a  liquid  glue  like  Le  Page's. 
To  the  right-hand  lower  corner  of  each  sheet  should  be  affixed  a 
label,  something  like  the  following,  which,  for  the  purpose  of 
illustration,  is  written  out  as  it  would  be  if  affixed  to  the  plant 
Chelidonium  : 
Herbarium,  C.  B.  L,owe. 
Bot.  Name,  Chelidonium  majus. 
Synonym,  Celandine. 
N.  O..  Papaveracese. 
.   Locality,  Tulpehocken,  4  22, '96. 
Each  specimen  or  all  of  the  same  species  may  be  enclosed  in  a 
sheet  of  white  paper  of  less  weight  than  that  upon  which  they  are 
mounted. 
All  of  the  species  of  the  same  genus  should  be  then  enclosed  in 
a  genus  cover  of  heavy  manilla  paper. 
The  name  of  the  genus,  with  that  of  the  natural  order,  should  be 
written  in  a  large  hand  upon  the  lower  left-hand  corner  of  the  cover 
next  the  back.  The  name  of  the  enclosed  species  can  be  written 
upon  the  lower  right-hand  corner.  The  genera  can  also  be  num- 
bered according  to  "  Gray's  Manual." 
