Ken,
"Challis flannel."
Per 1852 Webster's, "Challis" defined as "An elegant, twilled, fine woolen fabric, used for ladies' dress," citing "Encyc. of Dom. Econ."
"Flannel" defined simply as "A soft, nappy, woolen cloth, of loose texture."

(Dictionary cited is "An American Dictionary of the English Language ... by Noah Webster ...revised and enlarged by Chauncey A. Goodrich ... publishe by George and Charles Merriam, Springfield, Mass., 1852. 1152 pages.)