sentences:  However, the "Scotch" was eventually dropped as the AKC chose to use the terms "Rough" and "Smooth" to refer to these collies.It is generally believed that this occurred in an attempt to differentiate the show dogs from the common, or working, Scotch Collies.Following the continued popularity of this breed and their increased appearance in conformation shows, the Rough and Smooth Collies began to change in form, developing the flat skull and long narrow head familiar in today's collies, along with the more pronounced mane, or bib, of the Rough Collie.