348 MISSES K. FOOT AND E. C. STROBELL : RESULTS OF 



pair were killed. We were forced to discard some of the hybrids, and 

 selected this pair because the small percentage of eggs that hatched indicated 

 that they were not functioning normally in spite of the fact that the number 

 of eggs deposited in relation to the number of matings was quite normal. 

 The abnormally large percentage of eggs that failed to hatch may bear some 

 rehxtion to the fact that this female had probably deposited unfertilized eggs 

 before mating, for she was one of two females in a cage in which unfertilized 

 eggs had been deposited. 



See photo 11, Plate 28, for the male of this Fi hybrid pair. 



Before giving a summary of the l)reeding results of theGth and 7tli pairs 

 of Fi hybrids (Records IX. & X., p. 369) we must give a brief account of 

 some preliminary experiments. 



Two Fj hybrid females and three Fi hybrid males * were put in 

 Cage 34 immediately after they had reached the winged stage (between 

 July 9th and 12th). By August 6th none of these bugs had mated, and a 

 group of four unfertilized eggs had been deposited b}^ one of these females. 



The tv^'o females were then transferred to Cage 36, in which there were 

 4 Fi hybrid females and 4 Fj hybrid males that had not yet mated. At 

 2 P.M. of the same day two })airs were found mating, and were transferred, 

 while mating, to separate cages (Nos. 43 & 44). We believe these two 

 females were the two that were transferred to this cage from Cage 34, 

 though we have no proof of this. One of these pairs (Cage 43) mated 

 45^ hours, and on August 12tli mated again 6 hours. On August 15tli the 

 female died without having deposited any eggs. The second pair (Cage 44) 

 is the Fifth pair of Fi hybrids described above (Record VIIL). 



Cage 36 now contained 4 females and 2 males that had never mated. The 

 two males resembled bugs that are found in the fall after the breeding 

 season : the ventral surface had become hard and grey, instead of a fresh 

 green colour, which is typical at the breeding period. 



On August 15th we added to this cage the male that had mated August 12th 

 in Cage 43. Ten minutes after this male was put into Cage 36 he mated with 

 one of the four females, and the pair was transferred, while mating, to 

 Cage 46. They mated 15^ hours. There now remained in Cage 36 the 

 three females and the two males with grey venter, none of which had mated. 

 One of these females, however, had a fresh green venter and showed other 

 signs of functional activity. 



August 16th, we removed the two males with grey venter from this 

 cage (36) and added the male from Cage 46 that had just mated. At 



* Two of these males were killed August llth and the testes mounted for cytological 

 study. The bugs were preserved and are shown on Plate 28, photo 7. The third male was 

 killed August 13tli and preserved as a pinned specimen. 



