In the latest of a series of cost-cutting measures, Princeton University will lay off 43 staff members by this June, the university announced last week. At the same time, Princeton will reduce the hours of 18 employees. Affected employees were notified by e-mails starting Oct. 22, and Princeton President Shirley Tilghman said they would receive assistance from the university in finding new positions within the university or outside of it. The layoffs come as part of a two-year budget cut plan Princeton officials are following as a result of the university endowment’s 22.7 percent plunge, reported this fall. Princeton also offered a voluntary retirement program to 460 employees last summer; about one-third of employees agreed to retire through the program. Tilghman said the positions that have been eliminated will not necessarily be restored once the university’s finances recover.