I have just served up a Linnet shot two days ago. I next place in the
cage a bluebottle, one only, to avoid confusion. Her fat belly proclaims
the advent of a laying time. An hour later, when the excitement of being
put in prison is allayed, my captive is in labor. With eager, jerky
steps, she explores the morsel of game, goes from the head to the tail,
returns from the tail to the head, repeats the action several times and
at last settles near an eye, a dimmed eye sunk into its socket.

The ovipositor bends at a right angle and dives into the junction of the
beak, straight down to the root. Then the eggs are emitted for nearly
half an hour. The layer, utterly absorbed in her serious business,
remains stationary and impassive and is easily observed through my lens.
A movement on my part would doubtless scare her; but my restful presence
gives her no anxiety. I am nothing to her.

The discharge does not go on continuously until the ovaries are
exhausted; it is intermittent and performed in so many packets. Several
times over, the fly leaves the bird's beak and comes to take a rest upon
the wire gauze, where she brushes her hind legs one against the other.
In particular, before using it again, she cleans, smoothes and polishes
her laying tool, the probe that places the eggs. Then, feeling her womb
still teeming, she returns to the same spot at the joint of the beak.
The delivery is resumed, to cease presently and then begin anew. A
couple of hours are thus spent in alternate standing near the eye and
resting on the wire gauze.

At last, it is over. The fly does not go back to the bird, a proof
that her ovaries are exhausted. The next day, she is dead. The eggs are
dabbed in a continuous layer, at the entrance to the throat, at the
root of the tongue, on the membrane of the palate. Their number appears
considerable; the whole inside of the gullet is white with them. I fix
a little wooden prop between the two mandibles of the beak, to keep them
open and enable me to see what happens.

I learn in this way that the hatching takes place in a couple of days.
As soon as they are born, the young vermin, a swarming mass, leave the
place where they are and disappear down the throat. To inquire further
into the work is useless for the moment. We shall learn more about it
later, under conditions that make examination easier.

The beak of the bird invaded was closed at the start, as far as the
natural contact of the mandibles all