Pennaceous feather Pennaceous feather The pennaceous feather is a type of feather present in most modern birds and in some other species of maniraptoriform dinosaurs. A pennaceous feather has a stalk or quill. Its basal part, called a "calamus", is embedded in the skin. The calamus is hollow and has pith formed from the dry remains of the feather pulp, and the calamus opens below by an "inferior umbilicus" and above by a "superior umbilicus". The stalk above the calamus is a solid "rachis" having an umbilical groove on its underside. Pennaceous feathers have a rachis with "vanes" or "vaxillum " spreading
Calamus Swamp the blood sucking leech. Calamus Swamp Calamus Swamp is a public preserve located from Circleville in Pickaway County, Ohio, United States. It has a natural kettle lake/wetland and is owned by the Columbus Audubon, the local chapter of Audubon. Calamus Swamp includes the only known kettle lake in Central Ohio that is naturally vegetated and undisturbed. The kettle lake was made in the last ice age by the glacier that covered 2/3 of Ohio. When Ada May Burke and Sally V. May got the land, they donated it to Columbus Audubon, who then made it into a public preserve. According