A LOOK AT THE CONCENTRATION AND DISPERSION OF NEGROES IN THE CENSUS TRACTS OF NORTHERN AND SOUTHERN CITIES REVEALS THAT NEGRO RESIDENTIAL CONCENTRATION IS MORE THAN TWICE AS HEAVY IN THE NORTH. MORE THAN HALF OF THE NEGROES LIVING NORTH OF THE MASON-DIXON LINE ARE CROWDED INTO ONE-TWENTIETH OF THE CENSUS TRACTS, WHILE IN THE SOUTH LESS THAN HALF LIVE IN OVER ONE-TENTH OF THE CITIES' TRACTS. THE "BREAKING POINT"--THE ALLOWABLE MINIMUM OF AN UNDESIRABLE GROUP--FOR MOST NORTHERN NEIGHBORHOODS COMES WHEN 10 PERCENT OF THE FAMILIES LIVING THERE ARE NEGRO. SOUTHERN CITIES ARE MORE RACIALLY MIXED, BUT STREET FRONTAGE IN RESIDENTIAL AREAS IS USUALLY WHITE-OWNED. FAR FEWER THAN ONE OUT OF FIVE NORTHERN SCHOOLS ARE REALLY INTEGRATED. A GREAT DEAL OF SCHOOL TRANSFERRING WOULD BE NECESSARY TO INTEGRATE THE OTHERS, AND FEW CITIES HAVE ATTEMPTED THIS. THE SOUTH, BECAUSE OF MORE INTEGRATED NEIGHBORHOODS, FACES THE DIFFICULT SHORT TERM PROBLEM OF BRIDGING THE SCHOLASTIC GAP BETWEEN THE RACES. THIS ARTICLE IS PUBLISHED IN THE "EDUCATIONAL FORUM," VOLUME 24, NUMBER 2, JANUARY 1960. (AF)