Beginner Gardening: what are these?, 1 by abl_newbie

abl_newbie wrote:
Does anyone know what type of fungus/mushrooms these are? We had a heavy rain last night, and I KNOW these weren't in my flower bed yesterday. Is it possible for them to grow out that fast? There are DOZENS of them, in this flowerbed only. The "cap" part of them is anywhere from the size of a pencil eraser to nickel sized...They are silverish, blue-grayish in color...

1. How do I get rid of them? Preferably without any dangerous chemicals. We have a young Lab who eats EVERYTHING.
2. Are they harmful to my flowerbed or do they indicate other problems we might have in the soil?
3. They grew out through fresh mulch that we just purchased and spread about a week or two ago. Is this normal?

I would appreciate any info. Thanks!