
736 THE AMERICAN NATURALIST. [VoL. XXXVI. 
recorded in any locality is not always a safe criterion of the 
migratory movement of birds, because adverse meteorological 
conditions often tend to retard or stop the migrations and 
bring certain species under notice which, with favorable con- 
ditions, would have passed by unobserved. 
A previous paper by the author, *Hawk Flights in Con- 
necticut,” ! contained an account of flights of hawks which had 
occurred along the southern border of Connecticut during 
the autumn migrations, in which the results were presented of 
observations covering a period of nine years, from 1885 
to 1894. 
The present paper is an account of further observations on 
the migrations of hawks and on the effect of the wind on the 
migrations of various other species of birds. It is necessary 
to refer to the contents of the previous paper on the subject, 
and the principal facts given in it are as follows : 
It was shown that flights of hawks occurred in September 
of almost every year in southern Connecticut, consisting of 
different species, some of which passed along the coast singly, 
others in flocks of from twenty to two hundred. The hawks 
were most numerous at from one half to one mile inland 
from Long Island Sound, along the first low hills back from 
the coast. 
Twenty-two hawk flights were recorded in nine years, and 
in each case notes were made on the relative abundance of 
the different species of hawks seen migrating. A record was 
kept of the meteorological conditions on the days when the 
flights in question took place. It was found that on the 
days when the flights occurred the wind blew from the north 
or northwest, and usually with considerable velocity. On 
seven days the wind blew at the rate of over twenty miles 
an hour, and on eight other days not less than fifteen miles. 
The greatest flights occurred on three days, when the velocity 
of the wind was about forty miles per hour during part of the 
day. 
An explanation of the cause of these autumn flights of hawks 
was given, and the theory advanced has been fully verified by 
1 The Auk, July, 1895. 
