Thirty-one species (tables 6 and 7) reach the western limits of their distribution somewhere in Kansas. Most of these limits are in eastern Kansas, and coincide with the gradual disappearance of the eastern deciduous forest formation. Twenty-nine species are woodland birds, and few of these seem to find satisfactory conditions in the riparian woods extending out through western Kansas. The Wood Thrush is the one woodland species that has been found nesting in the west (Decatur County; Wolfe, 1961). Descriptively, therefore, the dominant reason for the existence of distributional limits in at least 28 of these birds is the lack of suitable woodland in western Kansas; these 28 are the largest single group reaching distributional limits in the State. Many other eastern woodland birds occur in western Kansas along riparian woodlands, as is mentioned below. Two species showing western limits in Kansas are characteristic of grassland habitats; the Eastern Meadowlark seems to disappear with absence of moist or bottomland prairie grassland and the Henslow Sparrow may be limited westerly by disappearance of tall-grass prairie. The Short-billed Marsh Wren, a marginal limnic species, reaches its southwesterly mid-continental breeding limits in northeastern Kansas. The species breeds in Kansas in two or three years of each ten, in summers having unusually high humidity. _Northern Limits Reached in Kansas_ Fourteen species (tables 6 and 7) reach their northern distributional limits in Kansas. Eight of these are birds of woodland habitats, but of these only the Carolina Chickadee is a species of the eastern deciduous woodlands; the other seven live in less mesic woodland. Three of these species (Chuck-will's-Widow, Scissor-tailed Flycatcher and Painted Bunting) have breeding ranges that suggest the northwesterly occurrences of summer humid warm air masses ("gulf fronts") and this environmental feature perhaps is of major importance for these birds, as it is also for the vegetational substratum in which the birds live. The Lesser Prairie Chicken and the Cassin Sparrow are the two birds of grasslands that are limited northerly in Kansas. Xeric, sandy grassland is chiefly limited to the southwestern quarter of Kansas, and this limitation is perhaps of major significance to these two species. The Scaled Quail and Roadrunner tend to drop out as the xeric "desert scrub" conditions of the southwest drop out in Kansas. TABLE 7.--ANALYSIS BY HABITAT-TYPE OF BIRDS REACHING DISTRIBUTIONAL LIMITS IN KANSAS