PLATE XII 



Fig. I. — Photomicrograph of a smear from a "wilted" gipsy-moth caterpillar. 



Fig. 2. — Photomicrograph of polyhedra clustering around a tracheal tube of a 

 gipsy-moth caterpillar. X 750. 



Fig. 3. — Photomicrograph showing various stages during the formation of polyhedra 

 in tissue nuclei of a gipsy-moth caterpillar. X 720. 



