I know they're called galls, and when I opened them one had a 3/4" white worm in it.

[raccoon]

Anybody know any more about these?

[Xyzse]

1. The insides looks like a nightmare version of a Kiwi.

[Orrex]

2. Are those unmitigated galls?

[pinboy3niner]

3. DUzy!

[raccoon]

5. I think they must be the mitigated kind. There are few of them around. :-) nt

[Chan790]

4. Yes. Those appear to be oak galls. They were used in the production of ink.

Your worm is a wasp larva. They infest the plant and force it to grow a wood-cocoon of sorts around them.

http://ento.psu.edu/extension/factsheets/galls-oak

You take them and leave them in a bottle with a rusty-nail and some water, it'll make weak ferrogallic ink that if reduced and a binder such as gum arabic is added will dry to a dark purple-black hue.

This is the most common ink of the middle ages, the ink used by monks to transcribe books.

http://en.wikipedia.org/wiki/Iron_gall_ink

[raccoon]

6. THank you! I had no idea they were used for that. nt

[rurallib]

10. so they had to have a lot of gall

to reproduce the bibles?

[Lucinda]

11. Fascinating stuff!

Thankie....I have to wonder what chain of events lead to someone figuring that out

[grasswire]

7. you cut it wrong

Doncha know that all gall is divided into three parts?

[dawg]

8. Ha!

Hail Caesar!

[mike_c]

9. the white worm is the larva of a cynipid wasp....

There are a bunch of Cynipidae wasp species-- tiny little stingless wasps-- and each produces a characteristic oak gall.

Here's one:

[undeterred]

12. Those look like my gall stones!

Wherever did you find them?