Fig. 15. Section through the fat body of a larva, 

 of Melanchra persicariae infected with a granu- 

 losis virus. Note the nucleus on the right ap- 

 parently liberating granules into the cytoplasm. 

 (Magnification: x 660.) 



Fig. 16. Section through a methacrylate- 

 embedded pellet of the tipula iridescent virus. 

 The pattern results from a transection made 

 tl: rough small crystalline regions oriented at 

 random. (Magnification: X 5800.) 



(Fig. 16 after Williams and Smith, 1957). 







4 



■ 



' 



Fig. 17. Section through part of a nucleus 

 of a blood cell from the larva of T. paludosa 

 infected with its polyhedrosis. Note the 

 peculiar vesicle surrounding each virus rod. 

 (Magnification: x 20,000.) 



Fig. 18. Sections through 

 virus particles from the 

 same disease as in Fig. 17. 

 Note a similar dilatation of 

 the membranes surrounding 

 the particles. (Magnific- 

 ation x 40,000.) 



