Handbook of Nature-Study · Lesson CXIII · Topic 18: Daddy-longlegs and spiders
113. The filmy dome
Goal: Your child can find a filmy dome web and describe how the little spider hangs beneath it and catches insects.
You'll need
- A woodland path on a sunny day in late summer or early fall
- A nature notebook and a pencil (colored pencils if you have them)
What's in the book
Comstock's story of the filmy dome, "like bubbles cut in half," shining with rainbow colors, held by guy-lines with a tangle of threads above, and the little spider hanging back downward beneath its top. Then Lesson CXIII's leading thought, method and five questions, and lines from "The Prisoner of Chillon."
The lesson, step by step
When and where
Comstock's method says it best:
On a sunny day in late summer or early autumn, while walking along woodland paths, the careful observer is sure to see suspended among the bushes or in the tops of weeds, or among dead branches of young hemlocks, the filmy dome webs.
Walk with the sun ahead of you or to one side: the domes shine only when the light hits them. In grass and woods, wear long pants tucked into socks, and check everyone for ticks when you get home.
Safety first
Spider safety: never pick up a spider you don't know. Look with a hand lens from a few inches away, touch webs only with a grass stem or a pencil, and never reach into a dark corner, woodpile or shed where you can't see.
Before you go, learn to recognize poison ivy ("leaves of three, let it be"), and poison oak or poison sumac where they grow. We never eat any wild berry, leaf or plant.
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:
One little spider spins a filmy dome, beneath the apex of which it hangs, back downward, awaiting its prey.
Find a dome
Where did you discover the filmy dome? What is the size of the dome? Does it open above or below? How is it held in place?
Are there many crisscrossed threads extending above the dome? If so, what do you think they are for?
The spider
Where does the spider stay? Is the spider large and heavy, or small and delicate?
What does the spider do if an insect becomes entangled in its web?
A small test
Throw a bit of stick or leaf upon a filmy dome web, and note what becomes of it.
Use a very small bit. Then read the leading thought aloud.
Nature notebook
Draw the dome like an upside-down bowl, with the tangle of threads above it and the tiny spider hanging under the top. Color the rainbow shine if you saw it.