354       Recent  Literature  Relating  to  Pharmacy,  {Am,jJu0iy^ifoh2arm' 
tained  in  the  German  yeast.  The  varieties  grown  considered  by  the 
author). 
B.  — Direct  sunlight  of  long  duration  caused  death.  25°-30°  C. 
is  the  most  favorable  temperature  for  their  development.  Young 
vegetative  yeast  cells  die  at  50°-6o°  C,  spores  at  6o°-65°  C. ;  in  a 
dry  condition  they  will  stand  a  maximum  temperature  of  1250  C. 
(Kaiser). 
C.  — When  dried  they  die,  only  the  spores  remaining  alive. 
D.  — Consumption  of  the  reserve  food  makes  the  protoplasm  more 
delicate. 
E.  — Small  additions  of  acid  promote  the  development  of  yeast 
(e.  g.,  0-002  per  cent,  sulphuric  acid,  M.  Heyduck).  Salts  act  as  with 
bacteria  and  fungi. 
F.  — Budding  yeast  is  a  little  more  sensitive  to  sodium  fluoride  than 
bacteria ;  with  0-005  Per  cent,  of  sodium  fluoride  their  fermentative 
activity  was  increased.  Mercuric  chloride  0-02  per  cent,  killed  the 
yeast  within  twenty-four  hours.  Silver  nitrate  the  same.  Formal- 
dehyde o*i  per  cent,  killed  within  sixteen  hours,  0-05  per  cent,  was 
very  injurious. 
G.  — Beer  yeast  was  not  killed  after  remaining  in  0  5  per  cent,  of 
sulphuric  acid  for  sixteen  hours,  but  the  cream  yeast  was  killed 
during  this  time  of  exposure.  In  o-i  per  cent,  the  beer  yeast  did 
not  in  the  above  time  appear  to  have  lost  any  of  its  generative 
power.  Also  injured  in  0  5  per  cent,  of  lactic  acid;  0-5  per  cent,  o 
sodium  hydrate  is  deadly  within  sixteen  hours,  o-l  per  cent,  is  not. 
H.  — Turpentine  water  (solution  1  :  75,000)  destroyed  the  genera- 
tive power  within  twenty-four  hours.  Thymol  water  (about  O-i  per 
cent.)  killed  the  yeast  within  two  hours.  I  per  cent,  of  carbolic  acid 
killed  the  pressed  yeast  within  fourteen  hours.  Chloroform  killed 
yeast;  10  per  cent,  alcohol  was  for  a  long  time  produced;  30  per 
cent,  killed  the  pressed  yeast  within  three  weeks. 
A.  — Protoplasms  of  the  lower  plants  and  animals. 
B.  — Spirogyra  was  rapidly  killed  in  water  heated  to  45°-55°  C 
Many  species  of  algse  live  in  the  Carlsbad  thermal  springs  as  well 
as  the  warm  spring  from  Ischia  with  a  temperature  ranging  from 
$3°_85°  C.  Sea- water  animalculae  die  at  35°  C,  fresh- water  amceba 
at  40°-45°  C.  (Kiihne).    Too  strong  light  is  injurious. 
C.  — Spirogyra  die  in  about  twelve  hours  when  in  dry  air  (over 
sulphuric  acid).    Absolute  alcohol  kills  immediately.    Many  lower 
