iiuii-latal  ca.,scs  of  blackwater  IVvcr.  When  granular  rasi  ,  na 
dclaclieil  willi  scparalion  of  epil hcluiiii  32)  the  possibility  n(  n 
few  red  cells  passing  from  the  blood  capillaries  adjacent  to  the 
exposed  basement  membrane  is  always  present  ami  jircsiiinaljly 
accounts  for  iheir  occasional  presence  in  small  numbers  in  blackwater 
fever. 
3.  In  the  exiicriments  on  rabliits  recorded  in  fable  35  it  was 
observed  that  the  blood  jilasma  after  haemoglobinaemia  and  haeniO’ 
globinuria  had  passed  off,  was  darker  in  colour  than  before 
experiment,  though  not  so  dark  as  in  lilackwater  fever.  Nevertheless 
j'cllowncss  of  the  sclerotics  was  not  observed  in  cx]icriiiiciilal 
haemoglobinuria  m  ralibits.  It  would  appear,  however,  that  llic 
orange  or  brownish  amber-colour  ol  the  blood  plasma  was  in  bnlli 
cases  of  similar  origin,  namely,  due  to  the  destruction  of  haemoglobin 
with  the  production  of  a  brownish  substance,  wliich  remains  in 
solution,  |ust  as  occurs  when  haemoglobin  is  firoken  up  in  a  test  lube 
miller  the  action  of  hydrochloric  acid  or  of  (piinine  biliydrochlimde, 
6.  The  h3'pothesis  of  a  primary  haemoglobinaemia  implies  11 
preceding  hiking  of  red  blood  cells.  .So  iar,  however,  the  site  in 
whn  h  this  hiking  may  occur  has  not  been  determined  (cp.  pp  15U 
to  n  11 1). 
7.  Haemoglobinaemia  is,  as  sueh,  unattended  by  pyrexia  .iiul 
general  constitutional  disturbance.  The  source  of  these  must  llim 
fore  be  sought  in  the  cause  of  the  haemoglobinaemia. 
'fuming  now  to  the  consideration  of  the  other  hyiiolhesis,  ihatn! 
a  primary  renal  haemorrhage  the  following  points  reejuire  to  be  taken 
into  consideration. 
I.  y\t  the  onset  we  arc  met  with  a  serious  difliculty.  II  Hif 
haemoglobinuria  of  blackwater  fever  were  clue  to  gloiuerulat 
haemorrhage,  the  blood  escaping  being  usually,  we  will  suppose,  lakdl 
at  once  owing  to  the  low  specific  gravity  of  the  urine  leaving  tl)H 
glomeruli,  then  to  account  for  this  haemoglobinaemia  we  must  assiiiiif 
that  the  dissolved  haemoglobin  so  formed  in  the  glomerular  cavil)' 
is  subse([uenlly  in  part  afisorbed  by  the  epithelium  of  the  urimfcroii'l 
tubules  and  then  finds  its  way  into  the  blood  plasma.  In  such  a  cast' 
the  amount  of  dissolved  haemoglobin  passing  into  the  blood  |)lasnw] 
would  sometimes  be  greater  than  that  passing  into  the  urine,  fui'Kl 
Case  7a  (p.  IQ5),  for  cxamjile,  the  blood  plasma  which  cuiilaiiicill 
