animal part in salad

I bought a bag of triple washed salad greens and prepared a salad. I bit onto a rather hard bite and tried to bite through it, but could not. Finally, I took the hard rubbery object out of my mouth. It had been chopped into an inch-square piece, but I could see what looked like a tentacle. The expert who examined it said it seemed to be some sort of mollusk and pointed out cilia and tentacle. He thought it looked like a piece of some water creature.

Needless to say I am afraid of prepared food and have gone back to less nutritious iceberg lettuce.

Is there any remedy for this?

Please see post below this one called "foreign object in food." Unless you were injured you most likely will get nothing.