What was the Confederate's Kentucky Line?

From: The Dark and Bloody Ground
http://www.civilwarhome.com/darkandbloodyground.htm

When the Civil War began, Albert Johnston, a good friend of Confederate President Jefferson Finis Davis, was assigned command of the Department No. 2, the Department of the West, the main defense of which was an army of ragged Tennesseans and Kentuckians known as the Kentucky Line. General Felix Kirk Zollicoffer was in charge of the men.

The troops had been called to duty on September 18th, 1861.