Handbook of Nature-Study · Lesson CXIV · Topic 18: Daddy-longlegs and spiders
114. Ballooning spiders
Goal: Your child can find the silk threads that cover a field in fall and describe how young spiders travel by floating on silk.
You'll need
- A grassy field or lawn on a warm, sunny October morning or evening
- A low wall, fence post or tall grass to watch
- A nature notebook and a pencil (colored pencils if you have them)
What's in the book
Comstock's story of ballooning spiders: fields carpeted with glistening single threads in autumn, and young spiders that climb to a high point, spin out silk and float away on the breeze like thistle seeds. Then Lesson CXIV's leading thought, method and four questions.
The lesson, step by step
When and where
Comstock's method: "These observations should be made out of doors during some warm sunny day in October." Early morning or late afternoon is best, when the sun is low.
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 young of many species of spiders scatter themselves like thistle seeds in balloons which they make of silk.
A field of silk
Stand so the low sun is ahead of you and a little to one side. Never look straight at the sun.
Look across the grass some warm sunny morning or evening of early fall, and note the threads of spider silk gleaming everywhere, not regular webs, but single threads spun from grass stalk to grass stalk, or from one object to another, until the ground seems glistening with silk threads.
Watch a balloonist
Find a small spider on a bush, fence post, or at the top of some tall grass stalk; watch it until it begins to spin out its thread.
What happens to the thread as it is spun out?
If the thread does not become entangled in any surrounding object what happens? If the thread does become entangled, what happens?
Be patient: a spider may tilt up its abdomen and wait for just the right breeze.
Why travel?
How far do you suppose a spider can travel on this silken aeroplane? Why should the young spider wish to travel?
Talk about what would happen if hundreds of spiderlings stayed where they hatched. Then read the leading thought aloud.
Nature notebook
Draw a tiny spider on a grass tip, tipped up, with long threads streaming into the air. Add the date and the weather.
Tip
What we know now: ballooning spiders have been caught high in the sky and found on ships far out at sea, so Comstock's "How far?" can mean hundreds of miles.