ate KUNKEL: FACTORS INFLUENCING TOXICITY OF 
value of potassium. The toxicity of potassium chloride in starch 
media is the same as was found for potassium nitrate in the same 
medium. 
TABLE II 
THE TOXICITY OF AMMONIUM CHLORIDE IN SACCHAROSE, GLUCOSE, LACTOSE, STARCH, 
ND PEPTONE MEDIA 
Saccharose 5% Glucose i Lactose 5% Starch 5% Peptone 5% 
Lee soe ae ae eee 
oo Growth G.M. Conc, | F2*"* | Gat. Cone, | Sro"t® | G, M. Cone, “Mer Gone aac 
NH,Cl 3 Days) NHsCl |, Days NHaCl 5 Days HyCl | 3 Days | NH,Cl | 3 Day 
.80 _ 1.30 ae ES 1.2 05 a 
5 = 1.25 mo) ~ I.I — | .90 
rie CS BO 1.20 oc 8 e 1.0 ee “85 «| 
05 [or £15 - Ad _- Ke) = Bots Mane eer 
60 | + 1.10 =— .6 _ 8 _ iy Weigh Ra ee 
55 | + 1.05 os * + 7 + 70°) 
ad Baie 1.00 + 4 + | 6 a 66 
45-4. | .90 + 3 + 5 + yee take 2 
.40 ao .80 a 2 + | 4 + SAO Ss Ae 
Fe i aleeg ee | -70 se t | 3 + ao oe 
Table II shows that the toxicity of ammonium chloride is not 
greatly different in the various media, though some differences 
are to be noted. It is least toxic in glucose and most toxic in 
lactose. The toxicity of potassium chloride in starch is approxi- 
mately the same as the toxicity of ammonium chloride in peptone, 
glucose and starch. The average limit concentration of am- 
monium chloride is .72 molar. When all of the media are taken 
into consideration, we see that ammonium chloride is more toxic 
than potassium chloride but less toxic than sodium chloride. 
Ammonium chloride is a possible source of nitrogen for Monilhia 
and it may be that for this reason it is less toxic than sodium 
chloride. 
The toxicity of sodium chloride in the different media as shown 
by Table III stands in sharp contrast with that of potassium 
chloride. While potassium chloride is least toxic in saccharose, 
sodium chloride is most toxic in this medium. It is hard to 
understand how two salts that are so much alike chemically should 
be so different as regards their toxicity in saccharose media. It 
is very interesting to see that potassium chloride, ammonium 
chloride and sodium chloride show almost equal toxicity in starch 
media, while in saccharose, glucose, lactose and peptone they 
SER ES Per eee alii = 4) eee” eee 
