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JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 15 



flying at night. During most of the time there were two observers, 

 so that the chances for a marked bee to pass unnoticed were reduced 

 to a minimum. Only full strength colonies were used in securing data. 



Nectar Gathering 



Since honeyflow and weather conditions have such a direct influence 

 upon the gathering of nectar, the time records secured under any given 

 set of conditions are not likely to be duplicated except under similar 

 conditions. During the period of observation in 1920, average 

 colonies stored about five pounds per day from white sweet clover, 

 Melilotus alba, while in 1921, average colonies gained only a little over 

 one pound per day from the same source. Weather conditions were 

 highly favorable for honey production in the former instance but were 

 only fair in the latter. Summarizing, it may be said that one set of 

 data was secured under very favorable conditions, whereas, the other 

 was obtained under conditions which were from mediocre to poor. The 

 data for field trips, hive stays and round trips have been plotted as fre- 

 quency curves in which the records obtained under favorable and un- 

 favorable conditions are compared. 



jninutes 



— I<IZI 



Fig. 3. Showing the frequency distribution of time records made by nectar carriers 

 under favorable and unfavorable honeyflow conditions. A, Field trip records. B, 

 Hive stay records. 



Of the records obtained for field trips made by nectar carriers in 1920, 

 31 percent fell within the 21-30 minute class, as shown in Fig. 3, A. 

 About 68 percent fell between 10 and 40 minutes, and 95 percent occupied 

 less than 1 hour. The mean time was about 34 minutes but the modal 

 or most frequent interval spent in the field was 26.8 minutes. 



*Modal values have been determined by use of W. I. King's formula given in his 

 "Elements of Statistical Method," p. 124. 



