306 
615. Violet-green Swallow. Tachycineta thalassina. L, 4-75. Plate LXIV B. 
Solid white below from throat to undertail coverts, and extending over face to include 
cheeks. Above: head to rump a rich velvety bottle green, washed with violet and bronze; 
rump and tail glossy, dark violet. Female similar but duller. Juvenile has the violet 
and green colours above replaced by ashy brown. 
Distinctions. Adult birds, or those with any indication of the violet and green above, 
are unmistakable. Juveniles with their pure white underparts can be mistaken only for 
the Tree Swallow. Sometimes differentiation between them may be difficult without 
specimens for comparison. The Violet-green is distinctly smaller and the brown of the 
upperparts is generally greyer and less brownish. 
Field Marks. With its black-appearing back and upperparts and pure white under- 
parts, to be mistaken only for the Tree Swallow. It has two excellent marks for field 
distinction, however. The cheeks are clear white, giving a white face that is lacking in the 
Tree Swallow, and in flight a sharp white spot shows on either side of the dark rump. 
The only other similar bird having such white rump spots is the White-throated Swift, 
so far found in Canada only in the lower Okanagan valley and a true Swift and not a 
Swallow. Note distinctions under family (page 302). 
Nesting. Nest in crannies of high perpendicular cliffs, frequently in holes in trees and 
occasionally in bird-houses or about buildings. Nest of grasses with feathers when pro- 
curable. » 
Distribution. Western North America. In Canada, British Columbia north through 
central Yukon. Probably adjoining foothills in Alberta. 
SUBSPECIES. The form of northern North America is the Northern Violet-green 
Swallow Tachycineta thalassina lepida. 
One of the loveliest of the Swallows. Its distinctive violet and green 
colours can rarely be discerned in life and to the eye it flashes in the sun 
in contrastive black and white. It is seen to best advantage in the narrow, 
steep mountain valleys of the interior, skimming close to the lower ground 
or high up in the blue in flocks that weave in and out amongst themselves 
in complicated pattern. Their nests may be up a steep mountain face, 
so high that only a white spot on the rocks at the entrance to a community 
niche marks the spot, and from the ground below the birds can hardly be 
distinguished with the naked eye as they enter or leave; even powerful 
glasses may leave the observer in doubt as to whether the moving specks 
are Swallows high up or flies lower down. The species will nest in boxes 
about the house when such cliffs are not immediately available. 
616. Bank Swallow, sand martin. Riparia riparia. L, 5-20. Plate LXV A. 
Above, dull brown; below, white with a sharp brown band across chest. Females like 
male. Juvenile similar, but the breast-band more diffuse. 
Distinctions. Dull brown instead of iridescent back; white underparts with decided 
dark breast-band, extending, in juvenilty, towards the abdomen. The complete breast- 
band will separate the Bank from the Tree or Violet-green Swallows that also have white 
underparts, and from the Rough- winged Swallows in which the white is less pure and the 
throat and breast are evenly suffused with ashy brown. 
Field Marks. A white-bellied Swallow with complete dark breast-band. A sturdily 
built bird. This character is most noticeable when flocks of mixed species are fined up on 
telegraph or other wires. 
Nesting. Nearly everyone has seen how quickly the exposed sides of a sand or gravel 
pit excavation become pitted with the small nesting holes of these Swallows. Too often 
the heedless small boy digs them out. Not only is this dangerous to the boy from the 
possibility of the bank caving, but it is a totally unnecessary disturbance of a very valu- 
able species. 
Distribution. Northern hemisphere. In Canada, across the Dominion, north to 
tree limits. Rarer on the west coast. 
617. Rough-winged Swallow. Stdgidopteryx serripennis. L, 5-75. Dark brown 
and white like the Bank Swallow (See Plate LXV A), but with breast and throat suffused 
with fight ashy-brown instead of crossed by a well-defined breast-band. 
