PLATE XIII 



Fig. I. — A silkworm polyhedron, after Prowazek. 



Fig. 2. — Two gipsy-moth caterpillar polyhedra adhering to each other. 



Fig. 3 to ID. — Polyhedra of gipsy-moth caterpillar cracking to pieces. 



Fig. II to i8. — Urate crystals of a gipsy- moth caterpillar. 



Fig. 19. — Polyhedron of a gipsy-moth caterpillar stained, showing a dark central 

 mass. 



Fig. 20. — Polyhedron of a gipsy-moth caterpillar stained, showing refractive 

 granules. 



Fig. 2 1 . — Chromatin lump in middle of pathological nucleus of a gipsy-motli cater- 

 pillar. X 950. 



Fig. 22. — Iron haematoxylin showing stained polyhedra of a gipsy-moth caterpillar 

 in a nucleus. X 950. 



Fig. 23. — Giemsa's stain, showing unstained polyhedra of a gipsy-moth caterpillar 

 in a nucleus and little granules. X 950. 



Fig. 24. — Fully formed polyhedra of a gipsy-moth caterpillar in a nucleus. X 950. 



Fig. 25. — Nuclear membrane ruptturing and allowing polyhedra of a gipsy- moth 

 caterpillar to escape. X 950. 



