That's what I thought it might be but these didn't have the
characteristic green color. Upon closer examination they appear to
have some sort of greyish coat that can be rubbed off to reveal the
characteristic green of aphids that I'm used to. It may be the cooler
weather is inducing them to produce some sort of insulation. I don't
know that much about aphids.

I do know that ants defend them from predators so I'm going to put out
some dishes containing a mixture made from one cup of boiling water,
two cups of sugar, and 1/2 teaspoon of borax to get rid of their
farmers.

Pat Kiewicz wrote:
James A. Bowery said:

Does anyone know for sure what bug this is?

http://video.google.com/videoplay?docid=-
8318991913753851458&hl=en

They're populating brussel sprout leaves but don't seem to be doing
much damage.

Some sort of aphid. They'll be getting inside the sprouts eventually,
probably also encouraging a black mold due to their excrement.

http://www.earthlife.net/insects/aphids.html
--
Pat in Plymouth MI ('someplace.net' is comcast)

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)