The older aethalia are brown.
The spores are spherical and are about 6um in diameter (this x600 image is about 86um in width). This is consistent with the 6 - 8um given for Lycogala epidendrum by Stephenson and Stempen (Myxomycetes: A Handbook of Slime Molds, 1994, page 136). You can also see some of the tubular pseudocapillitium in the background.
First 2 photos taken in the Wilderness, Whiteknights Park, Reading, UK, on 2012-05-06.