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egg batch in the 13th generation (Table 3-1). In terms of colony 

 productivity, the best combination of rearing temperature and larval 

 diet, was 27°C and "gator grits" (incubated and unincubated horn fly 

 medium) . 



Sex ratio . Perkins (1982) reported a malerfemale ratio in Lu . 

 shannoni of approximately 101:100. This is slightly less than the 

 114:100 male:female ratio observed in the first 13 laboratory 

 generations of Lu_. diabol ica . 



Colonies reared on "gator grits" (diets C and D, incubated and 

 unincubated hornfly diet, respectively) showed less male bias 

 (103:100) (Fig. 3-14). Due to the small sample size under diet 

 regimen E (standard sand fly diet, coarsely ground, applied moist), it 

 is difficult to draw conclusions, but it appears that the diet 

 produced a male biased population by prolonging the immature 

 development period. The longer the period was extended, the higher 

 the probability of mortality in the remaining individuals. Since most 

 of those remaining at the end of the cycle were females, fewer females 

 than males survived to the adult stage. The fact that fewer males 

 were produced on diet regimen B (standard sand fly diet with liver 

 powder, ground fine and applied dry) may indicate that males are more 

 susceptable than females to certain fungi encouraged by the addition 

 of liver powder to the diet. Further tests involving greater sample 

 sizes will be necessary to confirm these hypotheses. 



Longevity . Unmated males tended to outlive unfed, unmated 

 females by four to five days at 27°C and near 100% RH. The range of 

 longevity in both sexes was nearly the same (males 4 to 20 days; 

 females, 4-21 days). Blood-fed, mated females lived an average of one 



