We report on a study of the finite-temperature chiral transition on an
Nt=4 lattice for 2+1 flavors of Kogut-Susskind quarks. We find the point of
physical quark masses to lie in the region of crossover, in agreement with
results of previous studies. Results of a detailed examination of the
mu,d=ms case indicate vanishing of the screening mass of σ meson
at the end point of the first-order transition.Comment: LATTICE98(hightemp), 3 pages, 4 figure