The Idaho Springs siftings-news., 1911-05-20


anything out side of exact science,
and that Is that they have never been disputed
There is a unanimity of sentiment surrounding the
onslaught the house fly which ought either
to receive highest Endorsement arouse
darkest suspicion, just as the spirit is apt to
incline
The house fly proper Musca domestica Of the
order of the Diptera. Is grayish fly with mouth
formed for sucking up liquid substances.
1t has proboscs something like the trunk OF
elephant in miniature. and it's feet ternin-
ated each by pair of claws between which are
more or less membranous arolia or plantulae
which climb polished surfaces and also a puvil-
lus cushion. 1t does not bite. for that function
is reserved for stable fly which resembles 1t SO
closely to deceive anybody but entomol-
ogist Neither does 1t die upon the window pane
surrounded by the fungous efforescence IA
miliar to the disgusted housewife. That is the
habit of the cluster fly. which is somewhat larger
than the house fly. with dark-colored. smooth
abdomen and sluggish disposition.
Several other species bear a superficial like
ness to the true house fly and less
mistaken for 1t. All are inconsderate in num-
ber in comparison to the common pest, however.
that they may safely be disregarded in the dis
cussioh.
The great breeding place Of the house hy s
horse manure. 1t WILL 1t Is true, thrive to some
extent in other sorts of decaying animal and vege-
table matter but its partially for the stable ref
use so great that the vast proportion Of Its Off
spring may be considered originating in that
substance.
The fly lays Its eggs upon the manure. which
is its favorite larval flood. and a generation may
be bred in from ten to fourteen days. according to
the climate. There may be dozen generations
in a summer. An individual fly will average 120
eggs, and when the prevalence of horse manure
is taken into consideration Its widespread appli-
cation to farm lands in the way of fertilizer.
its presence In piles in or near city stables, Its
upon lawns and suburban gardens, the possi-
bilities in the propagation OF the fly will be read
fly seen to be past computation. 1t is even calcu-
lated that single fly. laying 12o eggs. will pro-
duce a progeny amounting to sextillions in one
season. This probably does not take into
1eideration accidents which operate greatly to
duce the supply
Some experiments have been made with a view
to calculating the number in which house-fy
larvae occur in manure but general average
can be struck. Twelve hundred house flies to the
pound OF manure 10 the result Of one observation.
Another showed 200 puparia in less than cubic
inch Yet perhaps no larvae can be found in
the greater part Of manure piles.
Because of his habits the house fly Is . walk
ing arsenal Of bacilli. The old notion that he
valuable as a scavenger is untrue. He will
prey on garbage and carry 1t away as part and
parcel of his tissue but he does not kill the germ
he absorbes. It has been proved that the bacteria
are not only taken into the ny and pass through
its body without any loss Of their active proper
ties but also that in all probability they multi
ply during their sojourn there.
These germs are deposited upon foodstuhs, and
eating utensils, pass into the human economy In
spite Of ordinary care. and II they are of a malev
olent type and the system which takes them in
is not strong enough to resist their action dis
tress disease and death apt to follow in their
wake In addition the fly also dissemnates
germs by carrying them upon his body. the cush-
ions of his feet and his wings.
Through the researches OF W. NJ. Eaton and c.
j. Mason 1t has been found that "the numbers of
bacteria on a single fly may range all the way
from $50 to $500 900" No general average can be
struck. A few million more or less will make
difference in the general result.
Because of its prevalence and its familiar
citation with man, Musca domestica has exception
al opportunities to distribute diseasebreeding bac
terra where they will do the most harm. A GER
tain genus of mosquito disseminates malaria but
he mosquito thrives only in localities especially
favorable to his propagation. There is good rea-