Natural History Bird’s Nest Fungi at Kew 18 October 2019 Ian Alexander Each cup is no bigger than your little fingernail. The cups grow on damp compost which the workers in Kew Gardens heap thickly under the trees. The “eggs” are called Peridioles, and they’re basically little bags of spores; they are splashed out of the cups by rain and the spores can then germinate. The family is the Nidulariaceae, which surprisingly is part of the Agaricales (normal-looking Basidiomycete mushrooms). species is the Common Bird’s Nest, Crucibulum laeve. One of the cups is still developing and is covered by a membrane. Yep, a different Bird’s Nest Fungus with a larger, greyer, frilly cup. This seems to be the Field Bird’s Nest, Cyathus olla.