Those are parasites on the tomato hornworm's back. If I find a hornworm with
parasites in my garden I usually move it somewhere it won't harm my plants
and leave it alone so the parasites will increase in number.
Marilyn
"ghb624" wrote in message
ups.com...
Please see photo, via link below. We caught a few of these guys today,
crawling around on the tomato plant vines. Wonder if anybody can
advise what the white things are, attached to the caterpillar's back.

http://img254.imageshack.us/img254/2...rpillaron6.jpg