By John S. McClenahen Initial claims for unemployment insurance totaled 350,000 on a seasonally adjusted basis last week, the U.S. Labor Department reported on Sept. 23. The figure for the week ending Sept. 18 was 14,000 higher than the previous week's revised figure of 336,000 and significantly above the 339,000 economists generally expected. The department's four-week moving average for initial claims, generally considered to be a better long-term indicator than the week-to-week numbers, also rose last week. At 341,000, it was 2,000 claims higher than the previous week's revised average of 339,000. The Labor Department also reported that 17,698 manufacturing workers lost their jobs in August as a result of 194 "mass" layoffs, actions that involved at least 50 workers at a single place of business. The August numbers were down dramatically, however, from those in July, when 145,895 manufacturing workers were out of jobs as a result of 885 layoffs, mainly as a result of the auto industry's model-year changeover.