I92I.] 

 Note E. 



Note F. 



Velocity of Migralnry Flight among Birds. 



231 



Observations taken in southern Palestine by stop--^atclies at 

 440 yards distance and timing birds Hying' between two 

 points aligned by posts. 



Observations made near Moutreuil in nortli-east France by 

 means of theodolites on a 1420-foot base and small 

 balloons to ascertain the velocity of the wind at the 

 altitude of flieht. All birds believed to be on misration. 



Ground 

 Species. Place. speed : 



m.p.h. 



Ravens S.Palestine. 32-39^ 



Eooks N.E.France. *4.5 



Rooks do. 39 



Rooks do. 



Rooks and Jack- do. 

 daws. 



Rooks do. 



Hooded Crow Rossitten. 



Jackdaw do. 



Chough Quetta. 



Starling do. 



Starling S.Palestine. 



Starling Rossitten. 



Rose-coloured Quetta. 



Starling. 



Finches Rossitten. 



38 



40 



39i 



31-5 

 39-6 



in 



43-49 



45-48.i 



46-5 

 38, 40i 



33 



Remarks. 



Eleven observations. Birds pass- 

 ing to and from roosting. Wind 

 calm. Altitude of flight 310- 

 840 feet. See note D. ^ 



Taken with air-sjieed indicator 

 from aeroplane. (R.A.F.) 



Altitude of flight 1740 feet. 

 Wind 17 m.p.h. side. See 

 note F. 



Altitude of flight 2120 feet. 

 Side wind of 31 m.p.h. See 

 note F. 



Altitude of fliglit 690 feet. 

 Slight side wind on ground. 

 See note F. 



Altitude of flight 2008 feet. 

 Head wind 12 m.p.h. See 

 note F. 



Average of observations on 

 20 birds. (Thienemanii.) 



Average on several birds. ( Th ie- 

 aemann.) 



Very strong head wind. See 

 note A. 



Thirteen observations. Wind 

 calm. See note A. 



Twenty-two observations. Alti- 

 tude of flight 120-325 feet. 

 Wind calm. See note D. 



A single bird. (Thienemann.) 



Two observations. Weather 

 calm. See note A. 



Six observations. {Tliiene - 

 mann.) 



Air-speed. 



