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
Calamus Creek (Wisconsin) are several DNR managed lands, including two areas of glacial habitat restoration. Calamus Creek (Wisconsin) Calamus Creek is a minor tributary of the Beaver Dam River, about long, in southeastern Wisconsin in the United States. Via the Beaver Dam, Crawfish, and Rock rivers, it is part of the watershed of the Mississippi River. Its watershed lies almost entirely within Dodge County with a small portion in neighboring Columbia County. Calamus Creek rises in west central Dodge County near the intersection of Mt. Pleasant and Van Buren roads and follows a highly winding, generally easterly course through Dodge County. It flows