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20
len, that sometimes is found in the bee-hives. Seen in the light
of our own findings this theory affords great interest.
Among theories of a still earlier date is the one of BENNEMANN and
HöBNnEr (see ZAnDer 28) particularly interesting. Paralysis worked great
havoc in the apiaries around Greifswald in the spring 1880. They give
the following description of the disease (pag. 22): »Es krochen dort eine
Menge Bienen auf der Erde umher, die je länger, je mehr zunahmen,
sodass sie zuletzt nicht mehr nach Tausenden, sondern fast nach
Schwärmen gezählt werden mussten. Diese Bienen waren alle nor-
mal gebildet, aber flugunfähig. Bei ihrem Hervorkommen aus dem
Stocke krochen sie träge auf dem Flugbrette hin, fielen beim Ab-
fliegen wenige Schritte vor dem Kasten auf die Erde und rannten
unter vergeblichen Versuchen zum Auffliegen den Tag hindurch
umher, zogen sich am Abend ermattet und entkräftet in Häufchen
zusammen und starben dann in der Nachtkühle; einige erreichten
aber auch noch den folgenden Morgen». It is added that the
bodies of the bees were »etwas aufgedunsen». When the bodies
were examined the abdomens were found to be full of spores of a
fungus which later on was identified with Mucor Macedo. The fun-
gus penetrated the abdominal wall especially between the tracheal
tubes and covered the body with a grayish coating on the outside.
The authors regarded this mould as the cause of the disease, but
ZANDER denies any connection between the fungus and the paraly-
sis assuring that Nosema brought about the disease. The Benne-
MANN and Hüsner theory, although not tenable is very interesting
as it is the first one to give expression to the belief that paralysis
is due to a fungus. It will be referred to once more in the follow-
ing.
A few other theories, totally imaginary, have sometimes found
ready listeners among practical bee-keepers, for instance the ones
that ascribe everything to »sour» water, or (GERsTUNG 10) to insuf-
ficient food during the time of the development of the bee. Even
more prevalent is the idea that pollen from certain plants causes
the trouble. There is hardly any plant that has kept clear from
suspicions. ZANDER quite correctly remarks (28, pag. 3) that while
these plants may occur over wide areas and thus be in a position
to bring on paralysis all over the disease is confined to certain
localities. Hence in German often named »Ortskrankheit».
The theory that Bacillus Gaytoni Cheshire is the cause of para-
lysis has come from America but, as Waite (25) remarks, »this is
Sunc,
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