Amongst the mulch

A friend told me about a display of fungi near Fish Creek Park last year, so of course I had to go and check it out : ) Taken on 29 June 2012, near the edge of the eastern end of the park. Wish I knew what kind of mushrooms these are - I love the patterns that form on the top surface of the caps. The look so much like some of the Easter Hot Cross Buns that I buy.

Any chance that these could be Cracked-Cap Mushroom / Agrocybe dura? Apparently, they are very common in wood mulch, which fits with my photo.