Here's more. Walnuts are bad! Since it is around holiday time, I thought I'd better show you this. I just found it.
Walnuts and Macadamia nuts also are hazardous to dogs. One ounce can lead to paralysis or weakness in a 20-pound dog. Immediately call a veterinary clinic if your pup eats something he shouldn't. Peanut Butter however is safe in reasonable doses!
http://www.treshanley.com/cic/hazards.html