PLAINS SONG FOR FEMALE VOICES by Wright Morris (David R. Godine: $10.95). This National Book Award-winning novel follows the lives of three generations of women on the Great Plains. Cora, the family matriarch, comes to the frontier as the unenthusiastic bride of Emerson Atkins in the late 19th Century. Hard-working and intelligent, this cold, closed woman is more capable of running a farm than displaying any affection toward her daughter and nieces. She bequeaths a decidedly mixed legacy to her descendants: a fair "English" complexion, a tall, slender figure and emotional problems. The next generation of Atkins women leave the family homestead for Chicago to pursue their education--and experience a freedom that Cora could never know. "Plains Song" forms an often eloquent chronicle of the changing roles of women in 20th-Century America.