Clematis vitalba (also known as Old man's beard and Traveller's Joy) is a shrub of the Ranunculaceae family. Clematis vitalba is a climbing shrub with branched, grooved stems, deciduous leaves, and scented greeny-white flowers with fluffy underlying sepals. The many fruits formed in each inflorescence have long silky appendages which, seen together, give the characteristic appearance of Old Man's beard. The grooves along the stems of C. vitalba can easily be felt when handling the plant.
Photograph and text courtesy of Wikipedia.