II 
These  plugs,  which  varied  considerably  in  diameter,  ranging  from 
30/U  to  8o/i,  gave  rise  to  the  brown  stippling  sometimes  seen  on  a 
cut  surface  of  the  cortex  of  the  kidney  (Fig.  61). 
i'JG.  38.  'transverse  section  of  medulla  of  kidney  during  suppression  of 
urine,  five  days  after  tiaenioglobinuria  had  ceased.  Hlackwater  Fever, 
Case  II,  About  half  of  the  collecting  tubules  are  partly  occupied  by 
darkly  staining  material,  which  in  some  places  appears  uniform  in 
aspect,  but  elsewhere  when  not  very  dense  is  seen  to  he  made  nji  ol 
granules  of  varying  size.  In  addition  epithelial  cells  can  be 
recognised  in  six  of  the  collecting  tubules.  The  collecting  tubules  are 
more  or  less  distended  and  their  epithelial  lining  is  correspondingly 
thinned.  The  epithelium  of  none  of  the  collecting  tubules  has  been 
shed,  'f'he  renal  epithelium  does  not  exhibit  degenerative  changes. 
The  blood  capillaries  are  with  very  few  exceptions  empty,  no  red 
cells  being  .seen.  The  interstitial  tissue  is  not  markedly  altered  in 
appearance.  No  malarial  pigment  is  recognisable,  Ilardened  in 
alcohol.  Stained  with  iron  almn  haematoxylin.  x  <35- 
H 
