Assertion: black swan's feather | /r/HasProperty | semi plumes
Facets:
Source sentences:
text: Other feathers that appear on birds are Semi plumes which appear half way between contour feathers and down feathers, Filoplumes which are small and are believed to have sensory functions, Bristles which are stiff hairs that appear around the eyes and mouth of some birds and function as protective hairs and Powder feathers which grow continuously and help keep the plumage clean.