A^'ctXrrPimm'}    Recent  Literature  Relating  to  Pharmacy.  503 
be  C^HgoOjg,  which  agrees  with  the  data  of  analysis,  and  still  better 
with  the  methoxyl  amount. 
Found  (Kohn).  C3SH58Oi5.  C^HeoOie. 
C  .  .  .  .  60-24-60-89  60-47  •  60-30 
H  .  .  .  .    7-54-  7*82  779  7*55 
CH20  .  .  3*4.  -  377  4'ii  3'89 
Accordingly,  strophanthin  differs  from  pseudo-strophanthin  by 
containing  three  molecules  of  water  more.  Both  substances  con- 
tain one  methoxyl  group;  but  while  that  of  strophanthin  is  found, 
on  hydrolysis,  in  the  carbohydrate  product,  that  of  pseudo-strophan- 
thin is  retained  in  the  ^-strophanthidin.  The  hydrolysis  in  each 
case  may  be  represented  by  the  following  equations  : 
Strophanthin.  Strophanthidin.  Strophanthobiose- 
methyl-ether. 
C40H66O19     =     (C2JH3807  +  2H20)    .;+  C12H2l01oCH3 
Pseudo-  Saccharobiose 
strophanthin.  ^-Strophanthidin.  (not  yet  isolated). 
c«y»°»|  QH3A.CHS      +  Q2H22o 
22^11 
Accordingly,  pseudo-strophanthin  would  be  the  methyl  ether  of 
a  substance  C29H3806  containing  one  oxygen  atom  less  than  stro- 
phanthidin. Those  substances  would,  therefore,  have  the  same  re- 
lation to  each  other  as  methoxybenzene  and  dioxybenzene : 
y  H  /OH 
x'  :.  X< 
xOCH3  xOH 
Strophanthin  and  pseudo-strophanthin  differ  in  melting  point, 
their  optical  rotation,  as  well  as  in  the  coloration  they  give  with  sul- 
phuric acid.  A  sample  obtained  from  Schuchardt  gave  a  red  color 
with  sulphuric  acid  like  ^-strophanthin,  though  in  other  respects  it 
perfectly  resembled  the  strophanthin  giving  a  green  coloration,  and 
that  may  have  been  due  to  the  preparation  being  old.  Some  years 
ago  the  observation  was  made  that  old  seeds  which  had  formerly 
given  a  green  coloration  with  sulphuric  acid  had,  after  keeping,  given 
a  red  coloration.  Perhaps  the  isolated  glucoside  may  be  liable  to  a 
similar  alteration,  though  the  specimens  I  have  had  for  three  years 
still  continue  to  give  the  green  color. 
A  further  difference  between  the  two  glucosides  is  apparent  in  the 
hydrolysis  caused  by  acid.    By  slowly  warming  strophanthin  with 
