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female often attempted to feed a second time, usually only for a few 

 seconds, before hopping to the floor of the feeding vial to rest and 

 digest the blood meal. Partially replete females, interrupted during 

 the first feeding, would feed on consecutive days until replete. 

 Droplets of clear liquid were excreted from the tip of the abdomen 

 during or shortly after feeding. Within about 24 hrs, the blood meal 

 turned from bright red to dark brown or black and dark spots of 

 excreted pigment could be seen on the white-plaster floor of the 

 container. In a few instances, feeding females took only clear fluid 

 (serum without red blood cells), having evidently pierced a lymph 

 vessel . 



Oviposit ion . Oviposition data for laboratory generations 1 

 through 9 and 13 are summarized in Table 3-6. A significant increase 

 in oviposition was observed in the 4th and subsequent generations, 

 coinciding with a change in rearing temperature from 24°C to 27°C 

 (ANOVA procedures, PR>F = 0.0001; Duncan's multiple range test, a = 

 0.05). The mean preoviposition period was 5.3 days and ranged from 

 3.7 days in the 9th generation to 8.2 days in the 7th. Midway through 

 the 8th generation a change was initiated in the holding procedure for 

 blood-fed females. Instead of placing the oviposition/rearing vials 

 in an open tray inside the environmental chamber, wet paper towels 

 were placed in the bottom of the tray and it was enveloped in a 

 plastic bag. This change increased the relative humidity in the vials 

 to near saturation and significantly decreased the preoviposition 

 period by as much as four days (ANOVA PR>F = 0.0001; Duncan's multiple 

 range test, a = 0.05). 



