Penny Peridioles

Day 49: Nidula candida is arguably the most common bird's-nest fungus in Pacific Northwest forests. Its cups are persistent, i.e., you can find them year-'round, although the "eggs" may be absent. The tiny lentil-shaped structures shown in this Penny Perspective are called peridioles ("peh-RIH-dee-uhls") and contain the spores of the fungus. In the case of N. candida, a viscous substance holds the peridioles in the cups until rain washes them free. If you look carefully at the photo, you can see a few "eggs" outside the cups on the wood. In some other species of bird's-nests, the peridioles are attached to the cups by tiny threads. In either instance, the spores seldom fall more than a few inches from the parent fungus, a factor which generally allows bird's-nests to colonize in compact "family groups."