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20
Verdauungskanal der Biene bei der Maikrankheit in Mitleidenschaft
gezogen ist, sodass in demselben — wegen Aufhörens der Muskel-
funktion eine Störung eintritt und sie den prall angefüllten Darm nicht
mehr sein Inhalts entleeren können.» Fortenıus claims the pollen
to be the cause of bee-paralysis. While it cannot be denied that
traces of phenolic substances may occur in pollen from plants
secreting ethereal oils the arguments of ZANDER are sufficient to
disprove the pollen theory. The theory of Bennemann and HUBNER
that Mucor Mucedo causes paralysis is likewise in need of some
modification. From the statements of these workers one gets the
impression that the organism in question killed the bees by some
sort af parasitism. This is of course wholly inconceivable. As the
spores of the fungus, however, freely germinate within the body of
the bees (see above) one has only to wait a few days after the insect
has been poisoned with the spores of Mucor to see the fungus break
through the abdominal wall covering the body with its mycelium
and spore masses.
4. Fungous growth in bees and bee-hives.
That the presence of moulds in the bee-hive is a matter of common
occurrence cannot possibly have escaped the attention of practical
bee-keepers. More particularly is this true of colonies that have
been wintered in hives poorly constructed or otherwise under con-
ditions favoring the growth and spread of moulds within the hive.
Of this we shall have more to say later on.
The number of fungi isolated and experimented with could easily
have been doubled but the almost constant occurrence of Mucor
Macedo and species of the genus Penicillium in bee-hives made it
desireable first of all to test the toxicity of these species rather than
to investigate the behavior of moulds only sporadically found in
hives. Nevertheless, extended investigations of these latter ones may
prove to be of some value. Only the pathogenicity of those moulds
known to cause mycosis in bees has, hitherto, been considered in
books dealing with bee-diseases. Howarp (16) was the first one to
call attention to aspergillosis in bees calling the disease »pickled
brood» or »white fungous disease». The fungus, Aspergillus pollinis,
attacked the larvae and pupae and transformed them into hard
mummies of whitish color. The disease has later on been identified
in Germany by Maaszen (see Baur) and by Baur (3) in Denmark.
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