Sinornithosaurus form from those found on birds from the same geological deposits. The body (contour) feathers were generally between 3-4.5 cm long and included two types: the first type are formed of several filaments joined together into "tufts", similar to modern down feathers. The second type, including those on the arms, were composed of rows of filaments ("barbs") joined together along a main shaft ("rachis"), making them similar in structure to modern bird feathers. However, unlike the wing feathers of flying birds, they did not have the secondary branches with tiny little hooks ("barbules") that flight feathers have, which allow the
A Donkey, 3 Rocks, and a Bird. of completion, plus the founder's mark for Will Willie. The Smithsonian Institution describes the work as abstract. Its condition was deemed "well maintained" by Smithsonian's "Save Outdoor Sculpture!" program in November 1993. A Donkey, 3 Rocks, and a Bird. A Donkey, 3 Rocks, and a Bird., also known as Donkey, Bird and Rocks and Donkey, Three Rocks, and a Bird, is an outdoor 1992 sculpture by Brad Rude, installed at Catlin Gabel School in West Haven-Sylvan, a census-designated place in Washington County and the Portland metropolitan area, in the U.S. state of Oregon. Brad Rude's "A Donkey, 3 Rocks, and