736 Field Museum of Natural History — -Zoology, Vol. IX. 



Eggs, 2 to 4. Size, about 2.40 x 1.82; dull white, scantily marked 

 with olive brown or cinnamon-brown. Bird, tail, rufous brown, no 

 white bars. Buteo borealis. 



Red-tailed Hawk. 



SECTION 2. NEST IN HOLE IN TREE, STUMP OR POST. 



PART I. EGGS LESS THAN i IN. LONG. 



Eggs, 5 to 8. Size, about .73 x .56; white, marked with pale rufous 

 brown or lavender brown. Sitta carolinensis. 



White-breasted Nuthatch. 

 Eggs, 3 to 6. Size, about .90 x .69 ; pale cream-brown or buff white, 

 marked and streaked longitudinally with chocolate brown. 



Myiarchiis crinitus. 

 Crested Flycatcher. 



PART 2. EGGS MORE THAN i IN. LONG. 



Eggs, 3 to 6. Size, about 1.16 x .82 ; pale bluish or greenish, marked 

 and scrawled with dark brown and black. Quiscalus qtiiscula csneus. 



Bronzed Grackle. 

 Eggs, 3 to 7. Size, about 1.38 x 1.14; pale tawny brown or brown- 

 ish white, marked and speckled with various shades of brown. 



Falco sparverius. 

 Sparrow Hawk. 



SECTION 3. NEST ABOUT DWELLINGS AND BARNS. 

 PART I. EGGS LESS THAN i IN. LONG. 



Eggs, 4 to 6. Size, about .77 x .54 ; white, marked with cinnamon or 

 olive brown. The slight difference in size will usually distinguish these 

 eggs from those of next species. Bird, tail forked; belly, rufous brown. 



Hirundo erythrogastra. 



Barn Swallow. 



Eggs, 4 to 5. Size, about .81 x .55; white, marked with cinnamon 



or rufous brown; usually more pronounced than in preceding species. 



Bird, tail not forked; belly, white. Petrochelidon lunifrons. 



Cliff Swallow. 



PART 2. EGGS MORE THAN i IN. LONG. 



Eggs, 3 to 5. Size, about 1.12X.80; usually bluish green (un- 

 marked), rarely with irregular spots of reddish brown. 



Planesticus migratorius. 



Robin. 



, Eggs, 2. Size, about 1.20X.85; pale olive buff or grayish white, 



thickly marked and speckled with brown and washed in places with 



purplish gray. Eggs sometimes deposited on roof of house, usually in 



fields, • Chordeiles virginianus. 



Nighthawk. 



