No. 374.] ACTIVITY OF A HIVE OF BEES. 93 
in large numbers, so that the weight of the hive sank rapidly 
to 880 gm. below the morning weight. From this time (10.30) 
the weight of the hive rose with almost as great rapidity as it 
had decreased, and passed the zero mark a little before 4 o'clock. 
It continued to rise until 8 P.M., when the record shows that 
1320 gm. of stores had been added during the day. 
The striking feature of this curve is the absence of the inter- 
mediate rise forming so strong a feature in the curve of May 8. 
But the difference seems explainable by the greater flow of 
nectar, evidently close at hand, which enabled the bees to 
quickly secure and return with their loads. The short flow of 
the middle of the day must certainly have been relatively very 
much more abundant than the aggregate power of the small 
laborers to dispose of it. 
In the other curves there is shown some slowness in starting 
to work in the morning. On June 4 (Fig. 1) the decrease in 
weight was comparatively rapid and continued at the same rate 
at which it began. At 7 o'clock, or two hours from the first 
weight, the hive began to increase somewhat slowly in weight 
until a little past 9. Then it increased rapidly and crossed the 
zero line about half an hour later. By 8 P.M. 4550 gm. had 
been added to the morning weight of the hive. 
The curve for July 20 is remarkable for the great decrease 
in weight, 1030 gm., and for the rapidity of the decrease, reach- 
ing, as it did, the limit at 9 a.m. Unlike the first minimum of 
May 8, this is the lowest of the two for the day. The reason 
for the difference is doubtless to be found in the greater flow 
of nectar on the latter day, as shown by the 990 gm. of stores 
added forthe day. Finally, the very precipitous rise in weight, 
from about 700 gm. at 5 to about 60 below the morning weight, 
-= during the next 20 minutes seems somewhat remarkable. 
If, now, the amount of stores be poor, it is evident that the 
different periods of strong honey flow for the season may be 
contrasted readily with the seasons of poor honey flow and 
` with the blooming time of different species of nectar-bearing 
plants. In connection with what Dufour tells his readers, the 
curves here reproduced show two periods of good honey flow 
and two of poor honey flow. The first of the latter periods 
