Essed . — The Panama Disease. /. 
35i 
spores, and the morphological peculiarities of the stroma, I propose to give 
it a place beside Ustilaginoidea . As far as I could find out we are dealing 
with a fungus not yet described, for which, on account of its great resem- 
blance to Ustilaginoidea and its harmfulness to the banana, I propose the 
name U stilaginoidella mnsaeperda. 
Bacteria. 
On account of the assertion of the expert of the United Fruit Co., 
that Bacteria were the cause of the Panama disease, I thought it necessary 
to ascertain — although the U stilaginoidella mnsaeperda was shown to be 
undoubtedly connected with the disease — whether Bacteria also had any- 
thing to do with the plague, as a primary or secondary cause, besides the 
fungus. The bacterial colonies were isolated in the ordinary way ; for the 
sake of convenience I shall indicate them by a and b. 
The a colonies appeared on one of the plates only, so that it proved to 
me at once that this bacterium could not be the Krankheitserreger. Pure 
cultures, however, were raised on banana agar with the special purpose of 
identifying the micro-organism. The colonies grew into roundish elevations 
of a citrine colour measuring i-ijmm. in diameter. On the fifth day they 
flattened down, showing a slight indication of sliminess on the top, and the 
original granular consistency was only discernible along the somewhat 
crenate margin. 
Stab cultures. Granular, yellow at the margin, merging into citrine in 
the centre, margin a little elevated. 
Bouillon cultures . Slightly turbid, with slimy sediment. 
Milk culture. Clotting after twelve days ; acid reaction. 
Potato culture. Citrine colour ; sinuous margin ; flat. 
Glucose culture . No gas formed. 
Staining . Gram-positive. 
Microscopic appearance. Round cocci of + 1 M diam., in some cases 
joined in packets of two or four. It is clear that we are here dealing with 
one of the forms of Micrococcus sidfureus , a common micro-organism in air 
and soil. 
The b colonies attained their maximum development after five days, 
presenting a great diversity of shape and size. Some were roundish, others 
irregular and lobed ; in the one case the margins were crenate, in the other 
case moruloid. The longest axis of a colony was about % mm. The colour 
was greyish white, with faint, bluish-green fluorescence on the agar. 
Stab culture . Thread-like, with a slight funnel-shaped dilatation near 
the surface ; granulation scarcely perceptible. After twenty-four hours a 
circular, shining, thin, slimy layer around the inoculation spot, upon which 
arose (forty-eight hours) the greyish-white colony, evenly spread ; agar 
fluorescing faintly blue-green. 
