JctTi8^8o^™  }  Aromatic  Products  of  the  Animal  Boay.  5 1 1 
ether.  The  portion  of  this  second  extract,  soluble  in  water,  gives  with 
basic  lead  acetate  a  precipitate  of  lead  parahydroxyphenylacetate,  from 
which  the  acid  may  be  liberated  by  sulphuretted  hydrogen,  and  purified 
by  crystallization  from  water  and  benzin  (m.  p.  148°).  About  J  gram 
of  crude  acid  is  thus  obtained.  Hydroparacoumaric  acid  (m,  p.  126  to 
127°)  is  occasionally  obtained  from  the  urine  by  the  same  process;  it 
separates  more  slowly  and  incompletely  from  hot  benzin  than  its 
homologue. 
Parahydroxyphenylacetic  acid  might  be  supposed  to  owe  its  origin  to 
an  amido  acid,  CgHgNOg,  homologous  with  tyrosin,  especially  since 
SchUtzenberger  has  detected  numerous  amido  acids  of  the  fatty  series 
amongst  the  decomposition-products  of  albumin  \  the  author  shows, 
however,  that  tyrosin  alone  is  produced  when  horn-clippings  are  boiled 
with  dilute  sulphuric  acid. 
In  order,  if  possible,  to  detect  some  of  the  transition-products 
between  hydroparacoumaric  acid  and  phenol,  5  grams  of  the  former 
were  administered  to  a  man  in  whose  urine  hydroxy  acids  and  phenols 
were  normally  present  only  in  minute  quantities.  On  subsequently 
examining  the  urine  it  was  found  that  the  greater  part  of  the  acid  had 
been  destroyed  ;  a  sma'll  part  ("8  gram)  was  obtained  unchanged  ;  and 
a  still  smaller  quantity  had  been  converted  into  a  phenol,  obtained  as 
an  ethereal  sulphate.  Parahydroxyphenylacetic  acid  could  not  be 
<letected. 
That  portion  of  the  ethereal  extract  from  urine,  obtained  as  above 
described,  which  was  sparingly  soluble  in  water,  contained  oily  acids 
which  reacted  with  nitric  acid  like  indole,  and  on  prolonged  contact 
with  putrescent  substance  yielded  a  considerable  amount  of  skatole, 
but  no  indole.  These  nitrogenous  acids  dissolve  in  hydrochloric  acid, 
and  are  resinified  when  boiled  with  it.  They  are  probably  the  sources 
of  skatole  and  indole  in  the  urine  and  in  decomposed  albumin;  since 
after  either  has  been  boiled  with  hydrochloric  acid  and  the  precipitated 
resins  removed,  the  basis  are  no  loi.ger  obtained  by  putrefaction  :  and 
putrescent  albumin,  not  so  far  decomposed  as  to  contain  indole  after 
being  agitated  with  ether,  does  not  yield  indole  on  further  putrefaction, 
whilst  the  ethereal  extract,  when  neutralized  with  sodium  carbonate  and 
diluted  with  water,  yields  that  base  on  standing  in  the  incubator  for 
six  days. — Jour.  Chem.  Soc.^  Sept.,  1880,  p.  648. 
