Feathered dinosaur the deciduous sheath, forming a tuft of unbranched barbs with a basal calamus. Stage III consists of two developmental novelties, IIIa and IIIb, as either could have occurred first. Stage IIIa involves helical displacement of barb ridges arising within the collar. The barb ridges on the anterior midline of the follicle fuse together, forming the rachis. The creation of a posterior barb locus follows, giving an indeterminate number of barbs. This resulted in a feather with a symmetrical, primarily branched structure with a rachis and unbranched barbs. In stage IIIb, barbules paired within the peripheral barbule plates of the barb
Calamus, Iowa Calamus, Iowa Calamus is a small town in Clinton County, Iowa, United States located on the historical Lincoln Highway, which was the first transcontinental highway for automobiles across the U.S.. Calamus is the only town in Olive Township and had a population of 439 at the 2010 census, which was an 11.4% increase from the 2000 census. Calamus was named after Calamus creek, which received its name from the great quantities of sweet flag growing in it, derived from the botanical name "Acorus calamus", commonly called Sweet Flag or Calamus. In July 1858 the first railroad was built west from