233 
1921.] Velocity of Migratory Flight among Birds . 
Ground 
Species. Place. speed: Remarks. 
m.p.h. 
Lammergeier . Quetta. 79| Gliding to food at angle of 
12 degrees to horizontal. 
Strong side wind. See note A. 
Lammergeier . Italy. *110 Bird nose-diving to escape from 
a pursuing aeroplane. Obser¬ 
vation taken with air-speed 
indicator. (R.A.F.) 
White Stork . Mesopotamia. *48 Birds on spring passage at 4200 
. feet over Baghdad. Birds drew 
in their necks and legs when 
machine was near. (R.A.F.) 
Grey Heron . France. under *45 By air-speed indicator. (R.A.F.) 
Gannets . Eastbourne. *48 By air-speed indicator. (R.A.F.) 
Pelican . S. Palestine. 51 Altitude of flight 1240 feet. 
A side wind of 15 m.p.h. See 
note D. 
Geese . P 44*3 Altitude of flight 905 feet. 
Measured by theodolite. (Clay¬ 
ton, 4 Science,’ n. s., vol. v. 
No. 105.) 
Geese . France. *55 By air-speed indicator. (R.A.F.) 
Geese and Duck ... Mesopotamia. 42-48, Frequent observation by air- 
slightly speed indicator. Birds usually 
faster. on passage, but all below 3000 
feet. (R.A.F.) 
Geese . France. 50^ Altitude of flight 4210 feet. 
Head wind of 9 m.p.h. See 
note F. 
Duck . ? 47’8 Altitude of flight 958 feet. 
Measured by a special theo¬ 
dolite. ( Clayton , ibid.) 
Duck . Quetta. 51-59 Eleven observations. Wind 
calm. See note A. 
Brent Geese . Scotland. *45 By air-speed indicator. (Wynne.) 
Mallard . P *50 By air-speed indicator. Birds 
believed to be on passage. 
(Wynne.) 
Mallard . France. under *50 By air-speed indicator. (R.A.F.) 
Teal.... S. Palestine. 44 Single bird flying low and 
leisurely. See note E. 
Houbara Bustard. Quetta. 42^ A single bird. Wind calm. 
See note A. 
* Air-speed. 
SER. XI.-VOL. 111. 
R 
