The mason-fly is also a ball-maker, but she carries her load and
builds an elaborate nest. This insect belongs to the order
"Hymenoptera," and is of the Ichneumon tribe, being a variety of
upward of four hundred species of that interesting fly.
The whole tribe of Ichneumon are celebrated for their courage; a
small fly will not hesitate to attack the largest cockroach, who
evinces the greatest terror at sight of his well-known enemy; but
the greatest proof of valor in a fly is displayed in the war of
the ichneumon against the spider.
There is a great variety of this insect in Ceylon, from the large
black species, the size of the hornet down to the minute
tinsel-green fly, no bigger than a gnat; but every one of these
different species wages perpetual war against the arch enemy of
flies.
In very dry weather in some districts, when most pools and
water-holes are dried up, a pail of water thrown upon the ground
will as assuredly attract a host of mason-flies as carrion will
bring together "blow-flies." They will be then seen in excessive
activity upon the wet earth, forming balls of mud, by rolling the
earth between their fore feet until they have manufactured each a
pill.
