570 
Peptones. 
Am.  Jour.  Pharm. 
NOV.,  1886. 
solutions,  nor  by  ammonium  sulphate ;  they  are  completely  precipitated 
by  tannin,  potassio-mercuric  iodide,  phosphomolybdic  acid,  phospho- 
tungstic  acid,  and  picric  acid.  A  5  per  cent,  solution  rendered  faintly 
alkaline  by  soda  has  the  following  additional  properties  : — 
Reagent. 
Acetic  acid  and  ferrocya- 
nide  of  potassium. 
Normal  lead  acetate  
Basic  lead  acetate  
Mercuric  chloride  
Copper  sulphate  (5  per 
cent). 
Platinic  chloride  (5  per 
cent). 
Chromic  acid  
Ferric  chloride  
Ferric  acetate  and  con- 
centrated H2S04. 
Nitric  acid  
Boiling  with  concen- 
trated HC1. 
Millon's  reagent  
Buiret  reaction  
Fibrin-antipeptone. 
At  first  clear;  later  a  trace 
of  opalescence. 
First  drop  nothing;  more, 
well-marked  opales- 
cence. 
Dense  opalescence. 
First  drop  nothing ;  more, 
dense  opalescence. 
At  first  clear;  later,  a  fee- 
ble opalescence,  disap- 
pearing with  excess  of 
reagent. 
Feeble  opalescence  with 
excess. 
Nothing. 
Opalescence  disappearing 
on  small  excess. 
Brown-red  color. 
Yellow  color. 
Color  darkens  a  little. 
A  white  precipitate  turn- 
ing to  a  dirty  yellow  on 
heating. 
Well  marked. 
Fibrin-amphopeptone. 
Opalescence  less  marked. 
Opalescence  less  dense. 
Opalescence  denser. 
Nothing. 
Nothing. 
Nothing. 
Nothing. 
Brown-red  color. 
Yellow  color. 
Color  darkens  a  little. 
A  white  precipitate  turn- 
ing to  bright  red  on 
heating. 
Well  marked. 
The  most  noteworthy  difference  in  the  above  table  is  the  behavior 
to  Millon's  reagent;  antipeptone  never  forms  leucine  and  tyrosine 
in  pancreatic  digestion,  whilst  amphopeptone,  which  contains  hemi- 
peptone,  does;  antipeptone,  moreover,  after  being  subjected  to  the 
action  of  trypsin,  yields  no  products  which  are  colored  red  or  violet 
by  bromine  or  chlorine  water,  as  hemipeptone  does.  Moreover,  when 
treated  with  sulphuric  acid,  antipeptone  did  not  yield  crystals  of 
tyrosine;  and  no  proof  could  be  obtained  of  its  presence  by  Hoff- 
mann's nor  by  Piria's  reaction.  From  antialbumid,  similarly,  no 
tyrosine  could  be  obtained  ;  whether  this  will  prove  to  be  a  general 
