1939] 
Study of Insect Flight 
7 
It is quite practicable to take a series of rate readings on one 
individual at 10-second intervals. With a series of speci- 
mens, where one observer has done all the handling and 
recording, the interval between readings has been about 40 
or 50 seconds ; if the recording is done by a second person, 
rates may be read on several specimens within a minute. 
It is felt that a great deal can be added to our knowledge 
of insect flight by the more extended use of this type of 
stroboscope. Much that is now conjectural in regard to the 
motions of the wings can be replaced by fact, easily and at 
relatively small expense. Even after high-speed photog- 
raphy has reached the state of perfection desired, and the 
day is not yet, the stroboscope will still have its own field of 
usefulness. There is need for extensive observation of living 
specimens under experimental conditions where photog- 
raphy may be neither necessary nor possible. For the 
photographer himself the stroboscope is a valuable adjunct 
which permits him to study in advance the rate and type of 
motion which he is about to attempt to photograph. The 
various shortcomings and difficulties to which attention has 
been called above are those which have presented themselves 
during six months work with this instrument on the prob- 
lems of insect flight and should serve to indicate the natural 
limitations of the method. 
The application of the stroboscope in the study of wing 
motion has been simplified by the generous cooperation of 
Professor H. E. Edgerton of the Massachusetts Institute of 
Technology. The writer wishes to take this opportunity of 
acknowledging his assistance and of thanking Professors 
C. T. Brues and A. C. Redfield, of the Department of Biology, 
Harvard University, for their encouragement in this work. 
List of References Cited. 
Germeshausen, K. J. & Edgerton, H. E. 1937. The Strobotron. 
Electronics 10 No. 2: 12, Feb. 1937. 
Landois, H. 1867. Die Ton- nnd Stimmapparate der Insekten in 
anatomisch-physiologischer und akustischer Beziehung. Z. wiss. 
Zool. 17: 105-184,187. 
Magnan, A. 1934. La locomotion chez les animaux I. Le vol des 
insectes. Paris, Hermann & Cie., 1934. 
Marey, E.-J. 1868. Determinations experimentales du mouvement 
des ailes des insectes pendant le vol. C. R. Acad. Sci. Paris, 67: 
1341. 
