April, '22j PARK: bees, time and labor factors 129 



nectar, this may account for the fact that the bees in these colonies 

 have longer lives and consequently are found in greater numbers. 



In 1921, over 3000 bees were examined to determine the length of 

 tongue, the individual carrying capacity, and the size of each bee. 

 The data secured was arranged in frequency distributions and the co- 

 efficient of variability was determined from these distributions. This 

 represented the probable variability of the group expressed on the per- 

 centage basis. The coefficient of variability in the size of the carrying 

 capacity was larger than either of the other two characters. Consequent- 

 ly, in order to determine the number of individuals necessary to be 

 examined to arrive at a definite conclusion, these figures will be based 

 on the coefficient of variability for the carrying capacity. If ten per- 

 cent is used as the difference to be measured, then the number of in- 

 dividuals required would be 32. In order to further safeguard these 

 measurements, it seems advisable to examine 40 bees from each colony, 

 as it appears that this number would be sufficient to be fairly represen- 

 tative and to give data accurately sufficient to form a definite conclusion. 



Summary 



A study of the data obtained in this experiment both in 1920 and 1921 

 indicates, first that there is a distinct correlation between the length 

 of tongue, carrying capacity of the bee, and the amount of honey stored 

 during the season; Second, that there is a distinct relation between the 

 nimiber of bees found in the colony in the spring and the size of the 

 above named physical characters. Third, it is very strongly indicated 

 that while it would be distinctly advantageous to a bee to excel in all 

 three of its physical characters, yet if it is deficient in any of these char- 

 acters, the disadvantage may be overcome if it possesses one of the 

 other characters to a greater degree. Since the probable error for the 

 coefficient of variability of each of these physical characters has been 

 computed, it will be necessary to examine 40 bees from any colony 

 in order to determine which colony of bees in a beeyard should be the 

 best producer. As this examination can be made early in the spring, 

 it will enable queen breeders to save one year's time in selecting the 

 colony which they are going to choose for the best producing quality. 



TIME AND LABOR FACTORS INVOLVED IN GATHERING 

 POLLEN AND NECTAR 



By Wallace Park, Ass't Chief in Apiculture, Iowa Experiment Station 



Time Factors 



Individual bees were marked and records kept of the time of de- 

 parture and return of each marked bee. Observations began early each 

 morning and continued without interruption until the bees ceased 



