PACE AND LAST 109 
birds of more rapid flight, and besides this, though 
they had descended from their lofty heights, they 
were, unlike the birds at Rossitten, still straining 
towards the land. Butin any case Dr. Thienemann’s 
observations, in point both of method and results, 
are interesting and valuable. The pace of no less 
than twenty Grey Crows flying at different times 
under varying circumstances was measured, and the 
average velocity, after allowance had been made for 
the wind, was 50°04 kilometres, or 31°5 miles per 
hour. Two Jackdaws had an average of 39°6 miles. 
A Starling flew at the rate of 46°5. Six Finches 
averaged 33:0, two Crossbills 37°5. This is about 
what we should have expected. But these definite 
observations are much better than the shrewdest 
of guesses. 
Velocity of Migratory Flights. 
There is good reason to believe that birds while 
migrating attain far greater velocity than they do 
in their ordinary flights. Let us take an example 
for which there seems to be strong evidence, though 
it is almost too marvellous to be true. The American 
Golden Plovers breed in Arctic regions, from Alaska 
to Greenland, above the limits of forest growth, and 
when autumn comes they pass over Nova Scotia, 
strike boldly out to sea, and, generally leaving the 
Bermudas well to the west, sail on over the ocean till 
they reach the West Indies. It is difficult to believe 
that these are merely stray birds that have been 
blown out of their course and are sailing on to death. 
One witness after another declares that he has seen 
flocks of them flying southward several hundred 
