228 
Psyche 
[Aug. -Oct. 
their several averages. 290.2, represents the total average num- 
ber of leaf fragments that were brought into the nest each 
minute. 
One hundred of these leaf fragments were taken from the 
transporting ants and weighed; their weight proved to be 1.164 
grams. If on the average a total of 290 . 2 fragments were carried 
into the nest each minute, the weight of vegetation added per 
minute must then have been a little over 3.35 grams. In an 
hour at this rate it would amount to 201 grams and in twelve 
hours to a little over 2.4 kilograms or some five &nd a quarter 
pounds. I do not know whether these ants work during the 
night. If they do so even at a lowered speed, the weight of 
vegetation added per day to the nest must be of course much 
more than five and a quarter pounds. The records here set down 
refer to daylight conditions toward the end of June. Incidentally 
it may be added that the rate of travel of an individual ant carry- 
ing a leaf fragment during the warm hours of the day in June 
varied from 1.5 to 1.2 meters per minute and averaged on ten 
counts 1 . 3 meters per minute. These incidental notes seemed 
worthy of record. 
