164 



The University Science Bulletin. 



SIXTH PAIR. 



Placed 2 female bugs in large stender marked No. 12, on July 20. 

 These bugs were from those Mrs. Wiley collected July 3. On 

 August 2, 2 nymphs appeared — an incubation period of 13 days. 

 The nymphs continued to appear, and their record is shown in 

 table 12 below. September 5 only 1 adult was to be found, and 

 yet it was impossible for the bugs to escape from the jar. Septem- 

 ber 6 both were gone from view, but later they were again above 

 the sand. In cloudy, threatening weather, the toad bugs bury 

 themselves beneath the surface and appear again in sunny weather. 



Table 12. 



SEVENTH PAIR. 



In stender marked 2a, placed a mating pair on May 25. On June 

 3, found an egg imbedded in the sand for about one-half of its 

 length. On June 13, found 11 eggs, 5 or 6 of which showed pink eye- 

 spots, so removed the adults to another stender. The eggs began 

 hatching June 17 and continued until June 28. The minimum in- 

 cubation period for some of the eggs was 15 days. 



