Chicago Quads Identical! Beat 3 Million to l Odds The quadruplet girls born Sunday in Michael Reese hospital are identical, a team of 10 doctors and other staff members disclosed yesterday. Simultaneously, Mrs.. Dolores Harris, 19, of 6218 Indiana av., announced that she and her husband, Bernard, 23, have decided to name their four daughters Sheen a Alice, Shawna Denyce, Sherry Julienne, and Shannon Nellie. Miss Audrey Johnson, a hospital social worker who is helping the Harris family adjust to its sudden increase, said the couple decided on the first names as "a form of togetherness." Their first child, now 15 months old, is named Shawn. Origin of Names Three of the middle names are combinations representing Michael Reese staff members and Nellie is for the quadruplets' grandmother, Mrs. Nellie Smith, who lives with her hus band. Dock, in the same building. Dr. Frank Rubovits, senior attending physician in the hospital's division of obstetrics and gynecology, said blood and tissue tests have confirmed that the children came from a single egg. He said the chance of this occurring "probably is about 3 million to 1." One Possibility Rarer The only rarer possibility, he said, would be the occurrence of two sets of identical twins, since this would represent "the same accident of nature occurring twice in the same pregnancy." He explained that identical births are accidents of egg division and not hereditary, as in the case of fraternal births from different eggs. Dr. William Alpern, attending physician, said be had been able to find only one other recorded birth of identical quadruplets. They were born in 1359 in England.