Handbook of Nature-Study · Lesson CXII · Topic 18: Daddy-longlegs and spiders
112. The orb-web
Goal: Your child can describe the parts of an orb-web (frame, spokes, sticky spiral), test which threads are sticky, and watch a spider build.
You'll need
- An orb-web with its spider, in a garden or meadow in late summer
- A pencil
- A spray bottle of water (optional)
- A watch or timer
- A nature notebook and a pencil (colored pencils if you have them)
What's in the book
Comstock's story of the orb-web, "the most intricate and beautiful in design" of all the work of small creatures: the frame and guy-lines, the spokes, the temporary spiral and the sticky spiral, and how the black and yellow garden spider builds it. Then Lesson CXII's leading thought, method, eleven questions, and a second set of ten questions on how an orb-web is made, with a diagram.
The lesson, step by step
When and where
Late summer and fall, in gardens, tall weeds and along porches. Comstock says spiders "may be seen making their webs in the early morning or in the evening." 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.
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:
No structure made by a creature lower than man is so exquisitely perfect as the orb-web of the spider.
Frame and spokes
Is the orb-web usually hung horizontally or vertically?
Observe the radii, or "spokes," of the web. How many are there? How are they fastened to surrounding objects?
Observe the silken thread laid around the spokes. Is it a spiral line or is each circle complete?
The pencil test
Touch any of the "spokes" lightly with the point of a pencil. Does it adhere to the pencil and stretch out as you pull the pencil away? Touch one of the circling lines with a pencil point, and see if it adheres to the point and is elastic.
How does the spider manage to run about its web without becoming entangled in the sticky thread?
Where is the spider?
Where does the spider stay, at the center of the web or in a little retreat at one side?
If an insect becomes entangled in the web, how does the spider discover the fact and act?
Watch one build
At dusk or just after dawn, find a spider starting a new web and time it.
How does the spider manage to place the supporting line between two points?
How many minutes did it take the spider to complete the web?
Then read the leading thought aloud.
Nature notebook
Draw the orb-web: frame lines, spokes and the spiral, with the zigzag band at the center if it has one. Write how many spokes you counted and how long the building took.