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
USS Calamus (AOG-25) as did the combatant ships. While at Okinawa "Calamus" was beached as a result of Typhoon Louise, 9 October 1945, refloated 24 October 1945, repaired and returned to service. Following occupation service, "Calamus" returned to San Francisco, California, 20 March 1946 and was struck from the Navy list (date unknown). She was decommissioned 15 May 1946, and transferred to the Maritime Commission 4 September 1946. Final disposition: she was scrapped in 1964. "Calamus" received one battle star for service in World War II. Her crew was eligible for the following medals: USS Calamus (AOG-25) USS "Calamus" (AOG-25) was a "Mettawee"-class