Handbook of Nature-Study · Lesson LXXXIX · Topic 13: Aphids and the insects that hunt them
89. The lace-wing and the aphis-lion
Goal: Your child can find lace-wing eggs on their silk stalks and describe the aphis-lion that hatches from them and eats aphids.
You'll need
- A plant with aphids, July until frost
- A hand lens (magnifying glass)
- A nature notebook and a pencil (colored pencils if you have them)
What's in the book
Comstock's story of the green, golden-eyed lace-wing: how she lays each egg on top of a stiff silk stalk, and how her young, the aphis-lion, sucks aphids dry with hollow jaws and spins a tiny round cocoon. Then Lesson LXXXIX's leading thought, method and six questions.
The lesson, step by step
When and where
Comstock's method: "Through July and until frost, the aphis-lions may be found on almost any plant infested with plant-lice; and the lace-wing's eggs or egg-shells on the long stalks are also readily found." Adult lace-wings often come to porch lights at night.
Keep the big idea in mind
Comstock's "leading thought" is the one idea the lesson is meant to lead to. Read it to yourself now, and save it to share at the end, after your child has looked and answered:
The lace-wing fly or golden-eyes, as she is called, is the mother of the aphis-lion. She lays her eggs on the top of stiff, silken stalks. The young aphis-lions when hatched, clamber down upon the leaf and feed upon plant-lice, sucking their blood through their tubular jaws.
Eggs on stalks
Look on leaves near the aphids for what looks like a fuzz of white mold.
When you see a leaf with some white mold upon it, examine it with a lens; the mold is likely to be the eggs of the lace-wing. Is the egg as large as a pin head? What is its shape? What is its color? How long is the stalk on which it is placed?
Why do you suppose the lace-wing mother lays her eggs on the tips of stalks?
The aphis-lion hunts
Look among the aphids for a small, flat, tapering larva with curved jaws, often carrying bits of trash on its back.
Watch an aphis-lion among the plant-lice. How does it act? Do the aphids seem afraid? Does the aphis-lion move rapidly? How does it act when eating an aphid?
Look without touching: it can give a tiny nip.
Two hunters
How does the aphis-lion differ in appearance from the ladybird larva?
If you can't find both, compare with the pictures in this lesson and in the ladybird lesson.
The golden-eyed mother
Describe the little lace-wing fly that comes from the cocoon. Why is she called, golden-eyes? Why lace-wing? Does she fly rapidly?
Comstock warns in her story that a lace-wing smells unpleasant if you pick her up. Then read the leading thought aloud.
Nature notebook
Draw a leaf with three lace-wing eggs on their stalks, an aphis-lion among aphids, and the green lace-wing with its gold eyes.
Afterwards
Comstock asks why the mother doesn't lay her eggs flat on the leaf. Let your child work out the answer: the first aphis-lion to hatch would eat its brothers and sisters.