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, Wisconsin Calamus, Wisconsin Calamus is a town in Dodge County, Wisconsin, United States. The population was 1,005 at the 2000 census. The unincorporated community of South Beaver Dam is located in the town. The unincorporated community of Lost Lake is also located partially in the town. The town was founded on January 22, 1846. According to the United States Census Bureau, the town has a total area of 36.5 square miles (94.7 km²), of which, 36.1 square miles (93.4 km²) of it is land and 0.5 square miles (1.2 km²) of it (1.29%) is water. As of the census of 2000,