Question
We found a large green worm in our yard about 4to4.5 inches long ,as round as a mans index finger It seems to have six small feet and four smaller ones towards the front of the body .Also has large claw like teeth and a brown like nose that looks like a beetle.The body is in segments like an armidillo beautiful light green in color and very soft and smooth. I would appreciate your comments since I have never seen anything this large in this area of the country. We live in southwestern Pa.

Answer
There are several large green caterpillars that live in the NE US. I am going to guess it is either the Polyphemus Moth or the Luna moth. Here is a web link to pictures of large caterpillars in your area. You should be able to ID which one you have from the pictures.
http://www.npwrc.usgs.gov/resource/insects/cateast/silkworm.htm