This mummy is enclosed in what is called a cartonnage, that is a case moulded on the figure.
"The Vanishing Man" by R. Austin Freeman
It was filled with mummies and cartonnages, ancient pottery and trinkets.
"The Voice in the Fog" by Harold MacGrath
The mummy itself was enclosed in a handsome cartonnage case laced up the back.
"Masques & Phases" by Robert Ross