62 



morphology is essentially developed) . In parts of the head 

 and in the petiole, however, the cuticle is completely destroy- 

 ed (Figs 13-16). In these areas, tissue fluids seep into 

 the space between the denuded hypodermis and the pupal sheath. 

 As the infection progresses, the fat body is diminished and 

 the brain shrinks (due to loss of lipids?). The mass of 

 these tissues, covered by hypodermis, decreases in size and 

 recedes from the pupal sheath, which is extended by fluid. 

 Jouvenaz and Hazard (1978) attributed the development of 

 clear areas in the head and petiole to destruction of the 

 hypodermis. More correctly, infection of the hypodermis 

 results in destruction or inhibition of formation of the 

 cuticle. 



The malformation of the eyes is also due to destruction 

 of the cuticle. The lens are part of the cuticle, and the 

 remaining components of the ommatidium (rhabdom and pigment, 

 retinular, and semper cells) extend between the lens and 

 a basement membrane. The lens are nonexistent in eyes in- 

 fected by B. dimorpha , and the rhabdoms and associated cells 

 become twisted masses. Perhaps the surrounding connective 

 tissue matrix is also destroyed. The eyes of pupae infected 

 by B. dimorpha develop after cuticle destruction has begun, 

 and are abnormal from the time they first become visible. 

 Thus, the derangement of the eyes is teratologic in nature. 



