9. Most of these little eggs, which are laid on moist walls of houses or preferably in animal stalls or on rotting wood or some other moisture-holding mold, are safe, but the eggs blown away by the wind, of these only a very few hatch. Nevertheless, nothing is lost; instead it has another wise purpose, including those that are inhaled by man and beast, often amounting to millions, with just one breath. But let us leave those that are destined for another purpose and return to those that do hatch.

10. How will these hatch?

11. Please note, when the sun has warmed the earth sufficiently, these little eggs begin to grow until they are so big they can be seen by a reasonably sharp eye as a whitish-gray flower pollen. Naturally, they are seen only at the spots where they have been laid by the fly. This is the time of hatching which happens thus: