fm-}        Methods  of  Water  Analysis.  in 
Series. 
IVXedium. 
Day  of 
Count. 
No.  Bacteria 
per  1  c.c. 
Gelatin  No.  i 
2 
3.000 
A 
"  "2 
2 
8,000 
Nahrstoflf  Heyden  agar 
10 
55,000 
Gelatin  No.  1 
2 
10,000 
B 
2 
24,000 
Nahrstoflf  Heyden  agar 
10 
30,000 
C 
Gelatin  No.  2 
2 
87,000 
Nahrstoflf  Heyden  agar 
10 
172,000 
D 
Gelatin  No.  2 
Nahrstoflf  Heyden  agar 
2 
10 
70,000 
108,000 
Gelatin  No.  1 
2 
8,000 
n 
"  "2 
2 
14,000 
Nahrstoflf  Heyden  agar 
10 
53.500 
Gelatin  No.  1 
2 
2.350 
p 
"         "  2 
i<  9 
2 
2 
4,800 
2,150 
Nahrstoflf  Heyden  agar 
10 
8,850 
Gelatin  No.  1 
2 
2,050 
G 
"  9 
2 
4,75o 
Nahrstoflf  Heyden  agar 
10 
34.500 
other  factor.     Given  a  certain  medium  and  environment,  some 
species  of  bacteria  will  develop  more  rapidly  than  others.     I  could 
illustrate  this  fact  by  numerous  instances,  but  will  cite  only  a  few 
from  my  own  records : 
Gelatin  plates,  third    day  count  3,050 
"  "      fourth   "      "  .  .  .   5,350- 
"  "      third     "      "  .  4,75° 
"  "      fourth   "      "   12,150 
f  "      second  "      "  8,000 
"  "      third     "      "   50,000 
"  "      second  "      "  .  .  2,350 
"  "      sixth     c<      "  4j50o 
"  "      second  "      "   4,800 
44  V      sixth     "      (i   13,150 
