81 



in both the transmission (Fig 29) and scanning (Fig 31) 

 electronmicrographs . The ridges may also be seen in the 

 immature spores in Fig 33. 



The pansporoblast membrane of B. dimorpha in worker 

 pupae was described by Jouvenaz and Hazard (197 8) as sub- 

 persistent and delicate, and ruptured during dissection 

 of the host. Mature spores are never, and immature spores 

 are rarely, seen in octets in smears. This is also true of 

 B. dimorpha from male pupae; however, the pansporoblast mem- 

 brane is quite persistent in specimens from female sexual 

 pupae. In the latter, mature spores are commonly seen in 

 octets in smears or aqueous extracts. 



Discussion 

 The diplocaryotic condition of meronts of B. dimorpha is 

 most difficult to observe. I have been unable to obtain 

 convincing photomicrographs of diplocaryia in these cells, 

 despite the use of high contrast technical pan film and 

 manipulation of staining protocols. After studying a very 

 large number of these cells with a microscope of excellent 

 quality, focusing up and down to distinguish depth of stain- 

 ing and faint curvatures, I have become convinced that these 

 cells are indeed diplocaryotic. Interestingly, I have con- 

 sistently obtained much superior definition in stains of 

 an undescribed, closely related microsporidium from S^. invicta . 



