ORNITHOLOGICAL NOTES FROM A SOUTH LONDON SUBURB. 
the sun rises they approach the earth more closely. During 
the dark hours they may have been travelling at a great 
height, and probably always do so, as they would find less air 
resistance and possibly fewer dangers at higher altitudes. 
SPECIAL FEATURES OF THE MIGRATION OF THE 
SWALLOW TRIBE. 
The migration of the Swallow tribe,—as witnessed over 
this district,—differs in some respects from that of all other 
species, as mentioned previously. 
Firstly, they appear to be essentially day travellers, since 
they are to be observed regularly every year on both the spring 
and autumn passages, though the numbers seen passing depend, 
as before mentioned, upon the general set of the wind, and the 
many,—as with all other species,—only when westerly winds 
prevail. 
Secondly, their course on arrival is as a rule N.W., and 
their direction when departing equally as a rule S.W.; ad- 
verse winds alone causing any deviation, and that but a slight 
one, from those courses. 
Thirdly, they travel, as might be expected from their 
great wing power, far faster than any other bird, often at what 
might be termed express speed, and apparently with their 
fastest pace against a stiff breeze. 
Fourthly, the extended period during which these move- 
ments continue seems peculiar to the tribe. Arriving parties 
may be seen any day, the wind being favourable, between mid- 
April and the end of May; whilst these May “rushes” i have 
observed in no other birds. The departing flocks also may 
be observed for some weeks, roughly speaking from mid- 
August to mid-October; the latest being presumably those 
that have summered furthest north. 
In conclusion, I would call attention to the accompanying 
Chart of 25 consecutive Octobers showing the daily direction 
and force (3 grades) of the wind, and also the dependence of 
the evidences of migration (also in 3 grades) upon those con- 
ditions. 
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