Eggs are laid in nests of some forty species of birds in Kansas; 39 of these are passerines. No preference for any one species is detectable; the most frequently parasitized species are simply the common species, and these are the kinds for which nesting records are easily gathered by man. In the following list of host species, the names marked with an asterisk are the conspicuously parasitized species. Mourning Dove, Eastern Kingbird, Eastern Phoebe,* Say Phoebe,* Acadian Flycatcher, Barn Swallow, Horned Lark, Carolina Wren, Rock Wren, Brown Thrasher,* Mockingbird, Catbird, Wood Thrush,* Eastern Bluebird, Yellow-throated Vireo, Bell Vireo,* White-eyed Vireo,* Parula Warbler, Yellow Warbler, Black-and-white Warbler, Kentucky Warbler, Louisiana Waterthrush, Yellow-breasted Chat, Yellowthroat, Eastern Meadowlark, Western Meadowlark, Red-winged Blackbird,* Orchard Oriole,* Cardinal,* Black-headed Grosbeak, Indigo Bunting,* Blue Grosbeak, Dickcissel,* Pine Siskin,* Rufous-sided Towhee,* Grasshopper Sparrow, Lark Sparrow,* Chipping Sparrow, Field Sparrow.* =Scarlet Tanager=: _Piranga olivacea_ (Gmelin).--This rare summer resident in northeastern Kansas occurs in deciduous forest and bottomland timber. Specimens taken in the breeding season and records of nesting come from Clay, Doniphan, Douglas, Wyandotte, Johnson, and Linn counties, but the species probably occupies the entire eastern third of the State. Dates of arrival in spring are from April 29 to May 25 (the median is May 11), and dates of departure in autumn are from August 4 to September 23 (the median is August 10). _Breeding schedule._--Six records of breeding fall in the period May 11 to June 20. _Number of eggs._--Clutch-size is about 4 eggs. Nests are placed 20 to 35 feet high in elm, linden, hickory, and walnut. =Summer Tanager=: _Piranga rubra rubra_ (Linnaeus).--This uncommon summer resident in eastern Kansas occurs in woodland. Specimens taken in the breeding season and records of nesting come from east of stations in Doniphan, Shawnee, and Montgomery counties. Dates of arrival in spring run from April 24 to May 18 (the median is April 29), and the species departs southward in September and October. _Breeding schedule._--Eleven records of egg-laying cover the period May 21 to July 20; the modal date for laying is June 5. _Number of eggs._--Clutch-size is about 4 eggs. Nests are situated ten to 20 feet high on horizontal limbs of large trees. =Cardinal=: _Richmondena cardinalis cardinalis_ (Linnaeus).--This species is a common resident in eastern Kansas, west to about the 99th meridian; west of this line the species becomes local and uncommon to rare. Habitat in the east is found in woodland, edge, second-growth and open riparian timber, and in the west the species is restricted to riparian growths, chiefly along the Republican, Solomon, Smoky Hill, Arkansas, and Cimarron rivers, and their larger tributaries.