80 
BIRDS OF DURHAM AND VICINITY. 
old stands. Although exceedingly particular in the selection of tene- 
ments, they often visit houses which they have no intention of occupy- 
ing, to the anxiety of the existing tenants. Tree Swallows and Blue- 
birds are thus often called to resist them, but never for long at a time. 
I observed an extraordinary case of this sort last June in Northwood. 
As I was passing a house I noticed a commotion among some Martins 
and ClitT Swallows. On stopping to ascertain the cause I found that 
the swallows had built several nests on the moulding under the eaves, 
and that the Martins were uninvited guests. A Martin had taken 
possession of one nest, and with his head sticking out of the entrance 
was talking volubly in a manner that made me feel certain his remarks 
were not less insolent than his act. 
Petrochelidon lunifrons. Cliff S\vallow. 612. 
Owing to their extreme gregariousness Cliff Swallows are very 
unevenly distributed. One farmers barn may have half a hundred 
nests ranged along beneath the eaves, while the barns of his neigh- 
bors are destitute of them. They begin to come from the south early 
in Alay — the fifth is the earliest I have noticed them — and are very 
soon engaged in repairing their curious mud nests. The majority 
leave early in August, and I have never seen one later than th.e twenty- 
second of that month. In their habits and looks they resemble Barn 
Swallows, though they lack the forked tail of that species, but are 
always readily identified by the brown spot on the rump. 
Chelidon erythrogastra. Barn Swallow. 613. 
Barn Swallows are niore abundant than any other species of their 
family and are quite evenly distributed. They have not the eminently 
social nature that belongs to the Cliff Swallow, neither have they the 
intolerance for others of their kind, which the Tree Swallow exhibits 
in the nesting season. A barn or shed is quite as likely to shelter a 
single pair as more, though several pairs frequently live together in 
harmony. I have known them to come as early as April 20, but more 
often it is a week later than this before they appear. They are the 
last of our swallows to depart in autumn, though they are all forced to 
go comparatively early on account of a lack of flying insects, which 
constitute the major part of their food. Only stragglers remain after 
the first week in September. My latest record is September 17. 
