Argued March 19, 1975 Decided May 7, 1975 Appeal from the Appellate Division of the Supreme Court in the Second Judicial Department, JOSEPH LIFF, J. Frederick Fagelson for appellant. George W. Percy, Jr., County Attorney (Patrick A. Sweeney of counsel), for respondents. COOKE, J. We review here the discharge of a social services investigator at the end of his 16th week of service, following his appointment from a competitive civil service list for a probationary term of 26 weeks, under county civil