destructiveness is seven years,
and therefore it may be accountable for the seven-year plague among the
hares and rabbits of the northern United States and Canada.

Possibly _Strongylus strigosus_ is all that stands between Canada and a
pest of rabbits like that of Australia. Just why this parasite is
inoperative in Australia, or why it has not been introduced there to
lessen the rabbit evil, we do not know. Mr. Seton declares that the
rabbits of his park were "subject to all the ills of the flesh, except
possibly writer's paralysis and housemaid's knee."

PARASITIC INFECTION OF WILD DUCKS.--The diseases of wild game,
especially waterfowl, grouse and quail, have caused heavy losses in
America as well as in European countries, and scientists have been
carefully investigating the cause and the general nature of the
maladies, as well as probable methods of prevention and cure. Mr. Geo.
Atkinson, a well-known practical naturalist of Portage la Prairie,
Manitoba, writes as follows to a local paper on this subject, which I
find quoted in the _National Sportsman_:

The question which has developed these important proportions during
the past year is that of the extent of the parasitic infection of
our wild ducks and other game, and the possibilities of the extended
transmission of these parasites to domestic stock, or even humanity,
by eating.

The parasites in question are contained in small elliptical cases
found underlying the surface muscles of the breast, and in advanced
cases extending deeper into the flesh and the muscular tissues of
the legs and wings. They are not noticeable in the ordinary process
of plucking the bird for the table, and are not found internally, so
that the only method of discovering their presence is by slitting
the skin of the breast and paring it back a few inches when the
worm-like sacs will be seen buried in the flesh.

These parasites have come to my notice periodically during the
process of skinning birds for mounting during the past number of
years, but it was only when they appeared in unusual numbers last
fall that I made inquiries of the biological bureaus of Washington
and Ottawa for information of their life history and the
possibilities of their transmission to other hosts.

Replies from these sources surprised me with the information that
very little was known of the life history of any of the
Sarcosporidia, of which group this was a sp