i 37 
the Spores of Copr inns sterquiiinus , Fr . 
stercorarius in liquid extract of dung without any trouble. He says: 
‘ Sie keimen sofort, wenn ein Tropfen Nahrlbsung —Mistdecoct —sie umgibt; 
auch wenn die Sporen langer als ein Jahr trocken aufbewahrt sind, werden 
nach wenigen Stunden schon die Anzeichen der Keimung deutlich.’ More 
attempts were therefore made according to Brefeld^s method. Hanging-drop 
cultures were made continuously for several weeks in solutions of varying 
strengths and at different temperatures, but without success. Eventually 
the spores in one culture commenced germinating vigorously. These were 
stained on the coverslip according to the method devised by Overton ( 22 , 
pp. 27-9). On staining, the mycelial tubes were found to be so thickly 
covered with Bacteria (PI. VII, Fig. 10) that their contents were indistin¬ 
guishable. The spores were again successfully grown in the same medium, 
but the Bacteria were always present. This suggested that perhaps the 
Bacteria played some part in the germination. Accordingly, part of the 
medium was sterilized by first passing it through a candle filter, and then 
heating it for two hours at 144 0 C. in the autoclave. 
Hanging-drop cultures were made with and without the Bacteria. In 
those with the Bacteria, germination always took place within twenty-four 
hours, but it never occurred at all without them. These experiments seem 
to show that the Bacteria are in some way necessary for the germination of 
the spores. This is again borne out by the fact that they were also present 
in the cultures in which the spores had first been passed through digestive 
fluids. 
The Bacteria. Brazilin was found to be a good stain for differentiating 
the Bacteria from the mycelium, but it gives no differentiation in the 
Bacteria themselves. They can, however, be detected under the microscope 
without staining. The Bacteria are very short rods measuring o«8 /x by 1*2 
in breadth and length. They occur in large numbers covering the mycelial 
tubes, particularly at those places where branching occurs, that is, at the 
centres of the greatest activity (Figs. 6, 7,10). In such cases it is impossible 
to distinguish the tubes underneath. Occasionally the Bacteria occur in 
chains or in groups of three or four, but more often they are scattered evenly, 
there being as many as 4,000,000 to the square millimetre. Lohnis ( 13 , 
p. 105) figures Bacteria in such groups and chains as common forms in 
manure from farmyards. 
The Bacteria develop quite well without the spores in liquid dung 
decoction, but so far have not grown in beer wort. They seem to grow 
better in cultures where spores are present. This suggests some kind 
of interdependence between the two, but of exactly what nature it is 
difficult to ascertain. Many attempts have been made to isolate the 
Bacteria on solid media, but so far without much success. In view of the 
fact that the Bacteria are abundantly present in the liquid extract of dung, 
this result is very peculiar. 
