32 BULLETIN 329, U. S. DEPARTMENT OF AGRICULTURE. 



In conclusion, there were only two stages found in the ovaries of 

 adults killed at the time of capture, either small, round, undeveloped 

 eggs in large quantity (stage 1), or round undeveloped eggs with 

 the addition of a very few large, fully developed eggs (stage 5). 

 This latter stage is presumably the result of a previous engorgement 

 and oviposition. 



CONDITION OF THE OVARIES OF NONENGOBGED ADULTS TAKEN ON ANIMALS. 



Six specimens, which had evidently just alighted and had not fed 

 on that particular animal, were taken at various times from mules' 

 ears. They lived from 2 to 47 hours after capture, and the condition 

 of the ovaries in all these specimens was typical of stage 1. There 

 was no development of the eggs within the ovaries, and the condition 

 seemed to be the same as in adults reared from pupse and dissected 

 shortly after emergence. 



CONDITION OF THE OVARIES OF PARTLY ENGORGED ADULTS. 



Twelve specimens were taken which had partly engorged (+). 

 The eggs within the ovaries of five of these specimens were not de- 

 veloped at all, and showed a condition corresponding to stage 1. 

 These lived from 16 to 30 hours after capture. Three specimens 

 showed the ovaries in a condition typical of stage 5, with from 1 

 to 4 fully developed eggs near the oviduct, and with the remainder 

 of the ovaries filled with the small round type. These individuals 

 lived from 12 to 21 hours after capture. The ovaries of two speci- 

 mens which lived for 52 and 53 hours, respectively, contained a large 

 number of eggs between stages 2 (PI. I, fig. 2) and 3 (PL I, fig. 3), 

 almost oval in shape, about 200 in all. Two adults were slightly 

 more engorged than the rest, though not quite half engorged. They 

 contained ovaries with eggs fully developed, of the same size and 

 shape as eggs freshly deposited, but in very small numbers as com- 

 pared with those found in adults dissected before oviposition. There 

 were about 30 eggs in the ovaries of one and 50 in the other, which 

 lived 45 and 47 hours, respectively. These adults had possibly en- 

 gorged once, oviposited, and then developed the remaining eggs in 

 the ovaries. 



In the condition of the ovaries of partly engorged adults these 

 two points are worthy of notice: (1) No development of the ovaries 

 took place unless the longevity of a specimen exceeded 40 hours; (2) 

 stage 5 recurred in three cases. 



CONDITION OF THE OVARIES OF HALF-ENGORGED ADULTS. 



Five half -engorged (-\ — \-) adults were taken. The ovaries of two 

 specimens contained eggs of the round type typical of stage 1. 

 They lived for 7 and 21 hours, respectively. One adult contained 

 ovaries filled with eggs of the typical oval shape (stage 3) in large 



