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incubation time of at least 3 days. Incubation times determined at 

 24°C and 27°C for individual eggs are given in Table 3-2. A highly 

 significant decrease in incubation time of nearly two days was 

 observed from the lower to the higher temperature (ANOVA procedures, 

 PR>F = 0.0001; student's t (z) test, a = 0.01). 



Of a total of 595 egg batches, 455 (76%) were fertile (had at 

 least one egg hatch) (Table 3-1). The percent fertile egg batches 

 ranged from a high of 91% in the 1st generation (progeny of wild- 

 caught females) to a low of 28% in the 7th. By the 13th generation, 

 the percent fertile egg batches had recovered to 88%, only slightly 

 less than that observed in egg batches from wi Id-caught females. 

 Hatching within fertile batches was roughly 40 to 50% for the first 

 five generations, then declined to 18.5% in the 8th. A reversal of 

 this trend was observed in subsequent generations, and by the 13th 

 generation, the percent hatch had doubled from the corresponding 8th 

 generation figure. The estimated hatch for the 16th generation was 

 around 50%. The percent hatch for individual eggs at 24°C and 27°C 

 was nearly the same at both temperatures (Table 3-2). 



Larvae and pupae . There are four larval instars of Lu. 

 diabol ica , each of which can be distinguished with the aid of a stereo 

 dissecting microscope (Fig. 3-5). Newly hatched, 1st instars are 

 about 0.5 mm long and 0.1 mm wide and grow to about twice their 

 original length and two to three times their original width before 

 molting. They are characterized by a conspicuous egg burster on the 

 vertex of the head capsule, and two long caudal bristles on the last 

 abdominal segment. Lateral and dorsal segmental setae are small and 

 inconspicuous. Prior to molting, the larva (all instars) becomes 



