Plate XLVI. 



These frames are two-faced, glazed, and labeled on both sides, the spaces being 

 cut from a dead black mat. They are intended for mounting in a swinging rack set 

 in the embrasure of a window, thus allowing the paper specimens to be examined 

 opaque or transparent at will. The frame illustrated contains various examples of 

 paper made from the pith and stalk of the corn plant, Zea mays. 



