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 Bird came down the Walk other evil forces.Then the narrator offers the bird a piece of crumb,but the bird neglects it and then it flies away. Helen Vendler regards the poem as a "bizarre little narrative" but one that typifies many of Dickinson's best qualities. She likens the poet to a reporter observing a murderer in the act, and later, pretending fear that the murderer may be dangerous to herself and must be mollified by a "crumb". The bird takes flight and Vendler regards what follows - the description of the bird in flight - as "the astonishing part of the poem". Vendler notes that