320 ane = 
figures and supposing that they can keep up fer twenty minutes. no 
matter how heavily laden on the return trip. the rate of speed on the 
outgoing would take them 10 or 12 miles from the home line.” : 
It is quite difficult to determine the rate of speed attained in flight 
by bees. Therefore any computation of the distance they go after 
honey which is based upon their supposed speed is liable to great error. 
The number of wing-strokes per second, 190, as recorded above, was 
obtained by Prof. Marey* by what is Known as the * graphic method.” 
A bee was held so that when its wings were in motion one of them 
would strike very lightly the surface of a revolving cylinder covered 
with smooth paper slightly smoked, and at the same time a style fixed 
in the end of a tuning-fork was arranged to record on the paper the 
vibrations of the fork. The tone of the latter being Known, and hence 
also the number of vibrations it makes per second. it was easy to com- 
pare the number of these actually recorded with the record of the 
bee’s wing for the same time, and thus arrive at the number of strokes 
the bee makes in a second. It is evident, however, that the friction of 
the bee’s wings against the paper must lessen somewhat the number 
of strokes, and indeed Prof. Marey observed that as he lessened this 
friction the velocity increased considerably. If the note made by the 
bee’s wings when she is in vigorous flight could be accurately deier- 
mined, the corresponding number of vibrations required per second to 
produce that pitch would represent the wing-strokes made by the bee 
eausing the sound. Dr. H. Landois* thinks the note of a bee in full 
flight ranges from A to C of the first and second leger of the treble clef. 
This gives over 400 vibrations per second. Ii, then, ‘+190 strokes per 
second would propel the bee forward at the rate of a mile per minute” 
(a claim by no means to be accepted as proven). and if Landois has 
determined the note correctly, over 2 miles per minute would be the 
speed attained. 
Conservative authorities are disposed to place the rate of speed at- 
tained by bees much below 30 miles per hour, even no more than 15 to 
20 miles, and nothing is better recognized than that bees when fatigued, 
when flying irom flower to flower, or when returning heavily laden to 
their hives, proceed far more slowly than when outward bound. Thus 
the calculation that they go 10 or 12 miles from home is plainly erroneous. 
However difficult it is to determine their rate of speed, and hence 
however erroneous any calculations based upon such determinations 
may be, it is not at all difficult to tell practically how far bees actually 
do go aiter honey. Apis mellifica has been introduced into regions 
where the species did not exist before. and careful observations have 
been made regarding the range of its flight, and also the yellow varie- 
ties have been taken to countries or localities where only brown or 
~ Animal Mechanism: A Treatise on Terrestrial and Aérial Locomotion. By E. J. 
Marey. (International Science Series), 1883. 
7 Die Ton-und Stimmaparate der Insekten. Von Dr. H. Landois. Zeitschrift fir 
wissenschafiliche Zoologie, 1867, p. 105. 
