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hundreds, covering many square yards of surface, so close together that 
their sides touch and are built together. It is interesting to note that, 
though sites are chosen apparently at random, and one occupied situation 
seems no more attractive than others adjoining, when the prevailing rains 
come, the nests, with their soluble walls, are invariably found to be on 
dry spots on the cliff face, in many cases the only dry spots in miles of rock 
front. 
613. Barn Swallow. Hirundo erythrogastra. L, 6*95 (Tail fork 1-75 deep). 
Plate LXIII B. Adult: with deeply forked tail. All steely black above. Below, 
reddish-chestnut, deepest on upper breast and throat. Bar across : forehead the same as 
throat. A somewhat broken and imperfect black bar separating throat and foreneck patch 
from the lighter underparts. Females: the same. Juveniles: similar, but lighter, and often 
with tail ungrown, less deeply forked, or almost square. 
Distinctions. The deeply forked tail of the adult is a certain specific distinction. Likely 
to be confused only with the Cliff Swallow, but more reddish below, face black; dark, 
dull chestnut forehead-bar instead of cream one; rump black like the back. 
Field Marks. The long “swallow-tail” is always diagnostic of this species. When 
this is not present, as in juvenile birds, the rufous cast to the underparts, white in the 
tail feathers, and solid black rump are good recognition marks. 
Nesting. The nest is far from being the beautiful structure the Cliff Swallow builds. 
It is largely made of mud mixed with grasses, lined with grass and feathers, and set on a 
support such as a rafter or beam; but often the slightest projection will be utilized as a 
foundation upon which to build. Some fanners ensure the presence of the birds about 
the place and induce them to nest where they will be unobjectionable by furnishing small 
supports for their nests close under the eaves of their bams or inside where they will be 
sheltered but can do no damage. 
Distribution. North America. In Canada, north to near tree limits. 
This is the Swallow commonly nesting in barns and outbuildings. 
It not only builds under the eaves, but enters the building and occupies 
the interior. Its long “swallow-tail” assists in making it perhaps the 
most graceful of all the Canadian Swallows. 
614. Tree Swallow, white-bellied swallow. Iridoprocne bicolor. L, 5*90. 
Plate LXIV A. Pure white below, from throat to tail-coverts. Above, solid steely 
black. Juveniles have iridescent black replaced by sooty brown. 
Distinctions. The adult uniform steely black above, and pure white below, is unmis- 
takable. Except from the Violet-green Swallow in British Columbia, juveniles can be 
distinguished by the purity of their white underparts and absence of any breast-band. 
A glance at the colours of the backs will separate adults from the Violet-green, but young 
birds may be difficult to recognize except by direct comparison with specimens. The 
Tree Swallow is a little larger, and the brown of the back is a little browner and less greyish. 
Field Marks. A contrastive black and white Swallow. Likely to be confused only 
with the Violet-green Swallow of British Columbia. It has two very distinct and easily 
recognizable field distinctions. The face and cheeks are black, not strikingly white, and in 
flight the rump shows solidly black, without white spots on either side that are character- 
istic of the Violet-green. 
Nesting. In Woodpeckers’ abandoned nest-holes or other cavities in dead stubs, or 
in nesting boxes, preferably near or over water. Lined with grasses and feathers. 
Distribution. North America. In Canada, north to near tree limits. 
Though normally using Woodpeckers’ holes in dead stubs over the 
water the Tree Swallow is easily induced to nest in boxes in the garden. 
The beauty of its bright iridescence and the grace of its flight make ample 
payment for the work of preparation, even if its presence were not an 
important safeguard against msects in the garden. The continued existence 
of the species is threatened through the growing scarcity of natural nesting 
sites and an effort should be made to supply the nests artificially. 
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