178 BOTANICAL GAZETTE [OCTOBER 
It fermented glucose, sucrose, fructose, lactose, galactose, and 
starch with abundant gas formation, but could not attack arabinose, 
cellulose, gum arabic, or calcium lactate. Similar to WINo- 
GRADSKY’S organism, it required some source of nitrogen, as pep- 
tones or proteins. It was an obligate anaerobe with large spores 
which had a greater diameter than the vegetative rod. 
In 1902 HAuMANN® published an interesting paper which gave 
an entirely new aspect to the subject. He stated that many 
common microorganisms could ret flax. He first studied the flora 
on the stalks of retted flax and isolated a number of organisms, 
among which were Bacterium coli-communis, Pseudomonas fluorescens, 
Bacillus subtilis, Streptothrix Forsteri, Penicillum glaucum, Cladospo- 
rium herbarum, Bacillus mesentericus fuscus, B. mycoides, B. termo, 
Micrococcus roseus, and Mucor mucedo. The mere presence of 
these organisms would not indicate that they functioned in retting. 
The preponderance of certain species, however, might indicate 
some relation to the retting process. Cladosporium herbarum, 
Bacillus mesentericus, B. subtilis, and colonies of Streptothrix were 
common. ‘To determine whether these organisms were important, 
HAUMANN inoculated sterile flax with pure cultures. The flax 
stalks were put into long culture tubes plugged with cotton. The 
tubes containing flax were heated to temperatures below 110° C. 
in the dry condition. He stated that three heatings under such 
conditions did not alter the flax. Retting was accomplished by 
using many of the common species of microorganisms. There was 
a difference in action, Pseudomonas fluorescens giving good results, 
while Micrococcus roseus was least satisfactory. HAUMANN con- 
cluded from this that all of the common bacteria were able to ret 
flax. Some of these bacteria were also able to split pectin. His 
results are unique in that they contradict those secured by many 
others and also those obtained in this investigation. In the light 
of some of the recent work on thermal resistance of the spores of 
anaerobic bacilli, HAuMANN’s method of sterilizing the flax is open 
to criticism. One would not expect these spores to be destroyed 
by a temperature of 110°, especially in the dry conditions. It is 
6 HaumANN, M. L., Etude microbiologique et chimique du rouissage aerobic 
du lin. hak ‘Past. Tost, 16:378-385. 1902. 
