27 
insufficiency  ot  means  and  methods  for  this 
purpose.  One  of  the  processes,  which  gave 
the  most  positive  results,  was  the  following: 
Fixation  of  very  small  pieces  of  tissues  in  al¬ 
cohol-sublimate  or  formol  (10  %).  Rapid 
passage  through  the  media  for  dehydration 
in  paraffin,  melting  at  56  or  60.  Staining  by 
QIEMSA,  picrocarmine-indigo-fuchsin  and 
hematoxylin-eosin.  We  do  not  want  to  explain 
all  we  did  in  this  line;  however,  we  may 
affirm,  that  we  tried  all  the  means  of  fixa¬ 
tion,  inclusion  and  staining.  All  of  these 
may  give  cause  for  objections,  in  all  one  may 
modify  something,  as  in  mycology  the  his¬ 
tological  methods  are  still  far  from  penect. 
The  parasite  presents  itself  in  the  tissues 
in  two  forms,  one  of  them  being  the  my- 
celian.  Notwithstanding  the  opinion  of  some 
mycologists,  the  mycelium  may  be  found  in 
the  tissues. 
The  photograph,  we  give,  is  typical. 
It  shows  sections  of  pulmonary  alveoli, 
where  mycelia  are  seen,  even  fructifying,  be¬ 
sides  some  leucocytes.  The  other  form  is  the 
yeast  form.  Typical  or  not,  the  latter  is  inte¬ 
resting  on  account  of  its  strange  aspect.  Its 
exact  value  may  escape,  when  one  is  not 
very  attentive.  The  forms  (see  the  drawings) 
look  perfectly  like  those  of  the  artificial  cul¬ 
tures  of  GODROWKA.  In  both  forms,  only 
the  outline  of  the  spherical  or  flattened  cells 
is  stained  and,  even  so,  feebly.  Their  com¬ 
plex  appears  as  a  mosaic. 
Some  of  these  figures  are  similar  to 
those  given  by  GU1LL1ERMOND,  at  page 
81  of  his  book  on  yeasts. 
Altogether  they  remind  one  of  the  zo- 
ogloeae,  which  HANSEN  studied  so  careful¬ 
ly.  Around  the  cells,  there  appears,  besides 
the  membrane,  a  protective  mucilagenous  or 
membraniform  involucre  (a  substance  much 
alike  fungin  or  metacellulose).  The  pheno¬ 
menon  is,  to  a  certain  degree,  identical  with 
what  we  see  in  WILL’s  cells,  but  for  the 
difference  that  here  the  proper  thickened 
cellular  membrane  plays  the  part  of  protec¬ 
tive  involucre  (GUILLIERMOND,  p.  81). 
Studying  the  forms  of  sputa  we  spent  some 
time  in  searching  for  the  cause  of  these  forms* 
A  point,  considered  capital,  cannot  be 
studied  too  much.  In  our  opinion,  the  above 
described  forms  represent,  as  a  rule,  resisting 
elements  like  the  saccharomycetic  forms  of 
the  parasite.  They  are  identical  with  those 
found  in  the  water  of  tubes  of  old  carrot-  or 
potato-cultures  and  on  GODROWSKA’s  me¬ 
dium.  The  forms  of  the  parasite  are  much  more 
complicated  in  the  media,  sperially  prepared 
for  the  Oïdium  brasiliense.  They  are  complex, 
various  and  abundant  in  the  parts  of  the  tissues, 
where  the  fungus  gets  the  upper  hand.  In  such 
parts,  the  growth  of  the  fungus  substitutes  the 
structure  of  the  parenchyma.  When  the  Oï¬ 
dium  expands  and  invades  the  tissues,  on  a 
large  scale,  the  prevalent  form  is  the  mixed 
one.  When  there  are  distant  and  circum¬ 
scribed  foci  of  parasites  and  the  struggle 
between  the  parasite  and  the  tissue  ends 
favorably  for  the  latter,  the  prevalent  form  is 
that  of  Saccharomyces,  as  happens  on  poor 
artificial  media.  The  polymorphism  of  the 
Oïdium  brasiliense  only  puzzles  observers 
not  versed  in  mycology.  The  facts  prove 
a  close  connection  between  all  the  forms 
of  the  fungus.  These  yeast-forms,  forms 
of  resistance,  are  common  in  lungsections. 
The  classical  yeast-forms  do  not  show 
anything  special.  The  mycelium  is  very  si¬ 
milar  to  that  of  certain  cultures  of  the  fungrs. 
Examining  a  hangingdropculture  (see  the 
photograph)  one  gets  the  impression  of  see¬ 
ing  the  parasite  as  in  certain  sections  of 
the  human  lungs  or  lymphatic  glands.  There 
is  a  cultural  form  of  mycelium,  whith  we 
did  not  find  in  the  tissues.  It  is  broad,  rich 
in  granules  and  poor  in  conidiospores.  Our 
photograph  shows  many  places  where  the 
network  of  mycelium  is  remarkable. 
The  mycelium  form  is  cylindrical,  with 
or  without  a  few  septa.  There  are  pseudo- 
mycelian  forms,  either  rectangular  or  cylin¬ 
drical.  We  may  observe  broader  mycelia  (5 
micra)  in  the  inner  part  of  certain  dilated 
bronchioli.  Some  mycelia,  seen  in  sections 
(specially  of  the  lungs),  enclose  small  anc 
distant  granules. 
