392 THE ZOOLOGIST. 
do arrive in the spring ‘‘on the south-east of England, between 
Kent and Norfolk,’ having come, I suppose, from Belgium or 
North-east France. If this is so, they may occasionally meet 
the bands leaving Norfolk by a south-easterly route at the same 
time of the year, but a wind which suited one party would be 
more or less adverse to the other, so it is not likely that they 
often clash. 
Mr. Eagle Clarke’s two volumes form an important work, on 
which great pains have been bestowed, and one which cannot 
fail to considerably advance the interesting but perplexing study 
of migration. Chap. viii. contains matter of much value on 
‘“‘ Weather Influences” on the birds, particularly as bearing on 
the spring emigratory movement from the British Isles. 
Mr. Clarke considers increase of temperature to be the main 
influencing factor with birds, and most observers will agree with 
him here, but he does not attach quite so much importance to 
the direction of the wind as I should have expected. 
Whoever studies either emigration or immigration of birds 
on the rounded and projecting coast of Norfolk must take the 
direction of wind into account; of that, after watching their 
movements for thirteen years in the neighbourhood of Cromer, 
I feel convinced. However, the position of our county is peculiar, 
for there is no other part of the Hast Coast which projects so 
much into the North Sea until Banff, in Scotland, is reached, 
and the wind may have more effect in Norfolk than elsewhere. 
