I believe what you are talking about is in fact called an inchworm in the fly fishing arena. Here is a picture of one.
[url=http://www.berkscountyweb.com/Birds/inchworm_1.htm:6f145]http://www.berkscountyweb.com/Birds/inchworm_1.htm[/url:6f145]

And here is a Fly Pattern for the same fly. They are on the leaves and hang over the streams in the summer time and drop into the water were the fish love to feed on them. I have also herd them called Oakworms. I do believe this is what you are looking for. Ron
[url=http://www.flyfishingconnection.com/patterns/flies/143/Inch+Worm:6f145]http://www.flyfishingconnection.com/patterns/flies/143/Inch+Worm[/url:6f145]