270 THE CANADIAN ENTOMOLOGIST 



were recorded as hatching when at least twenty-fi\'e larvae had 

 emerged. Oftentimes one or two larvae would appear in a vial 

 several days before the majority of the eggs were ready to hatch. 



For the determination of the percentage of sterility in the 

 eggs, those oviposited by ten difTerent increments of 100 females 

 were used, giving in all 50 vials of eggs. The number of eggs 

 failing to hatch when compared with the total number of eggs in 

 a vial gave the percentages of sterile and fertile eggs therein. 



Furthermore, 25 females were taken from the sticky bands to 

 see what efifect the tanglefoot on the body of the insect would 

 have upon the number of eggs deposited. 



Observations upon the number of males and females emerging 

 from a very limited area were ascertained by placing a light-tight 

 box over this surface and counting those coming up within. By 

 placing a shell vial in a cornucopia-shaped piece of cardboard in 

 the side of the box the adults emerging would seek the light of 

 the vial and could be counted from day to day. Unfortunately, 

 the possibilities of this phase of the experiment presented them- 

 selves too late for the collection of sufficient data upon which to 

 base definite conclusions. It would be interesting to learn whether 

 the relative proportion of males to females difTers materially dur- 

 ing the season of emergence. 



Average indoor temperatures were secured from a self-record- 

 ing thermometer by averaging the twelve hourly readings during 

 the day and night, respectively. 



Outdoor mean day and night temperatures were computed 

 from the daily readings taken by the physics department at 7 a.m., 

 2 p.m., and 7 p.m. The mean night temperature was assumed to 

 be the average of the readings of the thermometer at 7 p.m. and 

 7 a.m. The mean day temperature, however, was not so easily 

 obtained, but by giving the 2 p.m. reading double significance, 

 as this was probably the highest daily temperature reading, and 

 using this reading with those at 7 a.m. and 7 p.m. a fair average 

 was secured. Thus, in order to compute the mean day tempera- 

 ture on March 25, '17, which showed the following readings: 

 7 a.m., 43°; 2 p.m., 69.5°; and 7 p.m., 64°, we would add 43,69.5, 

 69.5, and 64 and divide by four, getting 61.5 . 



