NO. 2 DIMENSIONS OF FLYING ANIMALS GREENEWALT 9 



METHODS EMPLOYED IN OBTAINING DATA FOR TABLES 1-3, 

 FROM O. SOTAVALTA 



Wing frequency : 



All papers — "Flight tone": Sotavalta has the gift of perfect pitch and made 

 nearly all his measurements by the "acoustic" method. He reports a 

 possible error in his determinations of -5 to +1 percent. Data are given 

 which show his "acoustic" method to be in close agreement with direct 

 stroboscopic measurements. 



Total weight: 



1947 — Weights determined using "in most cases" a balance with a sensitivity 

 of ± 1 mg. after exposure of the insect to HCN vapor for 10 to 15 sec- 

 onds. 



19521 



igr^ ? As above, but with a more accurate balance. 



Wing length: 



All papers — Measured using a common millimeter rule with an accuracy of 

 zh ^ to 1 mm. Distance is the "direct distance from the wing tip to the 

 articular point." 



Wing area or total sustaining surface: 



1947 — Measured by tracing the contour of the entire insect with spread wings 

 on millimeter cross-section paper, "the wings then being fresh in their 

 assumed striking position straight aside." This gives the "total sustain- 

 ing surface." 



1952 — Measured as above but here the area of all wings alone was measured. 

 This gives true "wing area" of all wings. 



Wing weight: 



1952 — Weighings made on a microchemical balance with an accuracy of 1 

 microgram. For very small wings, several were weighed together and 

 the average weight computed. 



1954 — As above but with a torsion microbalance of 5 micrograms sensitivity. 



Moment of inertia of zvings : 



1952 1^ Determined by summation of the weights of small wing slices multiplied 

 1954 J by the square of the distance of the slice from the articular point. 



