1915] 
Cahn: Ecology of Wingra Springs Region 
167 
Pronge subis subis (Linnaeus). Purple Martin. 
Toward evening in the spring, summer, and fall the species 
enters the formation, and feeds on the wing over zone five. 
Hirundo erythrogastra Boddaert. . Barn Swallow. 
Like the martin, the barn swallow enters the formation only 
for food. None of the swallows breed within the formation, 
using the area merely as a most convenient feeding ground, and 
it is the abundance of insects that is the attraction; but for these 
there would probably be no swallows on the list. 
Iridoprocne bicolor (Vieillot). Tree Swallow. 
Quite common over zones three and five, especially in the spring 
and early summer. Feeds largely on midges. 
Riparia riparia (Linnaeus). Bank Swallow. 
Feeds over five, and may sometimes be seen circling over 
zone eight. 
Stelgidopteryx serripennis (Audubon). Rough-winged Swallow. 
Quite common over the swamp and along the course of the 
springs. 
Bombycilla cedrorum Vieillot. Cedar Waxwing. 
Not uncommon in zone six during the winter, and in zone 
seven (border) in the summer. Food consists largely of fruits, 
when available, often Smilacina racemosa or grape Vitis sp. 
Lanius ludovicianus migrans W. Palmer. Migrant Shrike. 
Rare within the formation, and seen only in six and seven. 
Vireosylva olivacea (Linnaeus). Red-eyed Vireo. 
Common during the late spring and summer in zone seven, 
where the species breeds. 
Vireosylva gilva gilva (Vieillot). Warbling Vireo. 
Found only on the spring migration, and then only in the heart 
of zone seven. 
Lanivireo flavifrons (Vieillot). Yellow-throated Vireo. 
Also a migrant, found as is the preceding species. 
Lanivireo solitarius solitarius (Wilson). Blue-headed Vireo. 
A migrant, not very common, in zone seven. All the vireos 
are characteristic of the higher trees. 
Mniotilta varia (Linnaeus). Black and White Warbler. 
Common only in the outer area of zone seven. 
Vermivora peregrina (Wilson). Tennessee Warbler. 
A few individuals seen for a short time during the spring migra- 
tion in zone six. 
